The following MATLAB commands define two ten-point signals and the DFT of each x1 = cos( [0:9]/9*2*pi); x2 = cos( [0:9]/10*2*pi); X1 = fft(x1); X2 -fft (x2); (a) Roughly sketch each of the two signals, highlighting the distinction between them.

The acceleration of the center of mass aGx is gsinθ/(1+I/mr^{2}), and the angular acceleration α is gsinθ/r(1+I/mr^{2}).

To find the acceleration of the center of mass aGx and the angular acceleration α of a hoop rolling down an incline at an angle θ, we can use two approaches. The first approach is to use the moment equation about the mass center G, which gives us aGx = gsinθ/(1+I/mr^{2}) and α = gsinθ/r(1+I/mr^{2}). The second approach is to use the moment equation about the contact point P, which gives us the same results. To ensure that the hoop rolls without slipping, we need to have a frictional force that is greater than or equal to the static friction coefficient μs times the normal force, which is equal to mgcosθ. Therefore, the required frictional condition is μs ≥ gcosθ/(1+I/mr^{2}).

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Answer:

Total time taken = 0.769 hour

Explanation:

using the velocity method

for sheet flow ;

Tt = [tex]\frac{0.007(nl)^{0.8} }{(Pl)^{5}s^{0.4} }[/tex]  

Tt = travel time

n = manning CaH

Pl = 25years

L = how length ( ft )

s = slope

For Location ( 1 )

s = 0.045

L = 1000 ft

n = 0.06 ( from manning's coefficient table )

Tt1 = 0.128 hour

For Location ( 2 )

s = 2.5 %

L= 750

n = 0.13

Tt2 = 0.239 hour

For Location ( 3 )

s = 1.5%

L = 500 ft

n = 0.15

Tt3 = 0.237  hour

For Location (4)

s = 0.5 %

L = 250 ft

n = 0.011

Tt4 = 0.165 hour

hence the Total time taken = Tt1 + Tt2 + Tt3 + Tt4

                                              = 0.128 + 0.239 + 0.237 + 0.165 = 0.769 hour

Answer:

d.

Explanation:

Branch circuits shall be sized in accordance with the maximum permitted.

The sizing of branch circuits ensure that they can safely and effectively carry the electrical load that will be placed on them. The National Electrical Code specifies the maximum ampacit  or current-carrying capacity of branch circuits based on the size and type of wire being used.

So, it important to size branch circuits correctly to avoid overloading the circuit which can result in overheating, fires, and other hazards. The contractors and other professionals responsible for installing and maintaining electrical systems should be familiar with the NEC requirements for branch circuit sizing and ensure that all installations comply with these standards.

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To calculate the variance of this project activity's estimated duration, we can use the formula:

Variance = [(b-a)/6]^2

where a is the optimistic time estimate, b is the pessimistic time estimate, and m is the most likely time estimate.

In this case, the optimistic time estimate (a) is 8, the pessimistic time estimate (b) is 27, and the most likely time estimate (m) is 16.

So, plugging these values into the formula:

Variance = [(27-8)/6]^2
Variance = 3.08

Therefore, the variance of this project activity's estimated duration is 3.08 (rounded to 2 decimal places).

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Answer:

Burj Khalifa is located in dubai UAE at over 828m

Explanation:

828 metres

Answer:

The Burji Khalifa, known as the Burj Dubai prior to its inauguration in 2010, is a skyscraper in Dubai, United Arab Emirates. With a total hight of 829.8 m and a roof hight of 828 m, the Burji Khalifa has been the tallest structure and building in the world since its topping out in 2009.

The treeFunc function counts the number of nodes in a binary tree.

The function takes a pointer to the root of a binary tree as input.

It initializes a counter variable "n" to zero, and two variables "left" and "right" to store the results of recursive calls on the left and right subtrees, respectively.

If the root is not NULL, it checks whether the left and right children are NULL or not, and increments the counter "n" accordingly (if either child is not NULL, the node is not a leaf).

The function then recursively calls itself on the left and right children, storing the results in the variables "left" and "right".

Finally, it returns the sum of "n", "left", and "right", which gives the total number of nodes in the tree.

If the root is NULL, the function immediately returns 0.

Therefore, the correct answer is (b) identifies the number of nodes in the tree.

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Answer:

attached below

Explanation:

Given data:

Gaged flow = 52 m^3 / sec

Depth covering drainage area = 1450 km^2

Develop a 24-hour rainfall duration unit hydrograph for the watershed using observed hydorgraph

Runoff flow = gaged flow - base flows

                   = 52 - 52 = 0 m^3/sec

For 18 hours time duration

Direct runoff volume ( Vr ) = ∑ ( QΔt1 )

where Δt = 6

           ∑Q = 3666 m^3/sec

hence Vr = Δt * ∑Q  = 79185600 m^3

Next we will convert the Direct runoff volume to its equivalent depth covering the drainage area

= Vr / drainage area depth

= 79185600 / 1450000000 = 5.46 cm

Next we will find the unit hydrograph flows by applying the relation below

[tex]Q_{1.0cm} = Q_{5.46cm} (\frac{1.0cm}{5.46cm} )[/tex]

where 14m^3/sec = [tex]Q_{5.6cm}[/tex]

input value back to the above relation

[tex]Q_{1.0cm} = 2.57 m^3/sec[/tex]

Attached below is The remaining part of the solution  tabulated below

and A graph of the unit hydorgraph for the given watershed

Note :

Base  flow total = 1560

UH total = 671.30

Answer:

Explanation:

A scenario is an actual sequence of interactions (i.e., an instance) describing one specific situation; a use case is a general sequence of interactions (i.e., a class) describing all possible scenarios associated with a situation. Scenarios are used as examples and for clarifying details with the client. Use cases are used as complete descriptions to specify a user task or a set of related system features.

Answer:

u need to plan it out

Explanation:

u need to plan it out

Answer:

use the turn 1 degrees option and put a repeat loop on it

Explanation:

u can add sound in ur loop

Answer:

A PULLY

Explanation:

HAD THIS ONE THAT IS THE CORRECT ANWSER

Answer:

The answer is B. a pulley

Explanation:

I hope I answered your question:)

Answer:

<:

Explanation:

Answer:

d

Explanation:

Answer:

Explanation:

From the given information:

The equation for applied stress can be expressed as:

[tex]\sigma_{app} = \dfrac{\tau_{CRSS}}{cos \phi \ cos \lambda}[/tex]

where;

[tex]\phi[/tex] = angle between the applied stress [100] and [111]

To determine the [tex]\phi[/tex] and [tex]\lambda[/tex] for the system

Using the equation:

[tex]\phi= cos^{-1}\Big [\dfrac{l_1l_2+m_1m_2+n_1n_2}{\sqrt{(l_1^2+m_1^2+n_1^2)(l_2^2+m_2^2+n_2^2)}}\Big][/tex]

for [100]

[tex]l_1 = 1, m_1 = 0, n_1 = 0[/tex]

for [111]

[tex]l_1 = 1 , m_1 = 1, n_1 = 1[/tex]

Thus;

[tex]\phi= cos^{-1}\Big [\dfrac{1*1+0*1+0*1}{\sqrt{(1^2+0^2+0^2)(1^2+1^2+1^2)}}\Big][/tex]

[tex]\phi= cos^{-1}\Big [\dfrac{1}{\sqrt{(3)}}\Big][/tex]

[tex]\phi= 54.74^0[/tex]

To determine  [tex]\lambda[/tex]  for [tex][1 \overline 1 0][/tex]

where;

for [100]

[tex]l_1 = 1, m_1 = 0, n_1 = 0[/tex]

for [tex][1 \overline 1 0][/tex]

[tex]l_1 = 1 , m_1 = -1, n_1 = 0[/tex]

Thus;

[tex]\lambda= cos^{-1}\Big [\dfrac{1*1+0*1+0*0}{\sqrt{(1^2+0^2+0^2)(1^2+(-1)^2+0^2)}}\Big][/tex]

[tex]\phi= cos^{-1}\Big [\dfrac{1}{\sqrt{(2)}}\Big][/tex]

[tex]\phi= 45^0[/tex]

Thus, the magnitude of the applied stress can be computed as:

[tex]\sigma_{app} = \dfrac{\tau_{CRSS}}{cos \phi \ cos \lambda }[/tex]

[tex]\sigma_{app} = \dfrac{2.00}{cos (54.74) \ cos (45) }[/tex]

[tex]\mathbf{\sigma_{app} =4.89 \ MPa}[/tex]

Answer:

20368.917N

Explanation:

Frictional force (F) is the product of the Coefficient of friction and the normal reaction.

F = μN

Coefficient of friction, μ = 0.2

Normal reaction = MgCosθ

Mass, m = 12 tonnes = 12 * 1000 = 12000 kg

N = 12000 * 9.8 * cos30

N = 101844.58

F = 0.2 * 101844.58

F = 20368.917N

To solve this problem, we can use the ideal gas law and the equation for polytropic process.

The ideal gas law is a fundamental law of physics that describes the behavior of an ideal gas. It relates the pressure, volume, temperature, and number of particles of a gas using the following equation:

PV = nRT

a) First, we need to find the mass of the carbon dioxide in the tank. The ideal gas law is:

PV = mRT

where P is the pressure, V is the volume, m is the mass, R is the universal gas constant, and T is the temperature. Rearranging for the mass, we get:

m = PV / RT

Substituting the given values, we have:

m = (200 kPa)(0.3 m3) / [(0.287 kPam3/kgK)(27°C + 273.15)] = 3.87 kg

So the mass of the carbon dioxide in the tank is 3.87 kg.

b) To determine the work done by the gas during the process, we can use the equation for polytropic process:

P1V1^n = P2V2^n

where P1 and V1 are the initial pressure and volume, P2 and V2 are the final pressure and volume, and n is the polytropic index. Substituting the given values, we have:

(200 kPa)(0.3 m3)^n = (4)(0.6 m3)^n

Dividing both sides by (0.3 m3)^n and taking the logarithm of both sides, we get:

log(200) + nlog(0.3) = log(4) + nlog(0.6)

Solving for n, we get:

n = log(4/200) / log(0.6/0.3) ≈ 1.235

Using the polytropic work equation:

W = (P2V2 - P1V1) / (1 - n)

Substituting the given values, we have:

W = [(4 kPa)(0.6 m3) - (200 kPa)(0.3 m3)] / (1 - 1.235) = 233.7 kJ

So the work done by the gas during the process is 233.7 kJ.

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The statement that is invalid is: "The final state is reachable from all other states."

This statement is incorrect because the final state is a state in which the object-oriented software has completed its execution, and it should not have any outbound transitions. Therefore, it should not be possible to reach the final state from any other state. The final state should only have inbound transitions from other states. On the other hand, the other statements are valid. The initial state should only have outbound transitions because it is the starting point of the object-oriented software. There should be an event and an action associated with a state transition to specify what triggers the transition and what happens during the transition. Every state should be reachable from any state to ensure that all possible paths through the software can be tested.

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Solution :

Assuming that the wire has an uniform temperature, the equivalent convective heat transfer coefficient is given as :

[tex]$h_T= \epsilon \sigma (T_s+T_{surr})(T_s^2 +T^2_{surr})$[/tex]

[tex]$h_T= 0.20 \times 5.67 \times 10^{-8} (1473+323)(1473^2 +323^2)$[/tex]

[tex]$h_T=46.3 \ W/m^2 .K$[/tex]

The total heat transfer coefficient will be :

[tex]$h_T=(250+46.3) \ W/m^2 .K$[/tex]

    [tex]$=296.3 \ W/m^2 .K$[/tex]

Now calculating the maximum volumetric heat generation :

[tex]$\dot {q}_{max}=\frac{2h_t}{r_0}(T_s-T_{\infty})$[/tex]

[tex]$\dot {q}_{max}=\frac{2\times 296.3}{0.0005}(1200-50)$[/tex]

        [tex]$= 1.362 \times 10^{9} \ W/m^3$[/tex]

The heat generation inside the wire is given as :

[tex]$\dot{q} = \frac{I^2R}{V}$[/tex]

Here, R is the resistance of the wire

         V is the volume of the wire

∴ [tex]$\dot{q} = \frac{I^2\left( \rho \times \frac{L}{A} \right)}{A \times L}$[/tex]

     [tex]$=\frac{I^2 \rho}{\left(\frac{\pi}{4}D^2 \right)}$[/tex]

where, ρ is the resistivity.

[tex]$I_{max}= \left(\frac{\dot{q}_{max}}{\rho} \right)^{1/2} \times \frac{\pi}{4}D^2$[/tex]

[tex]$I_{max}= \left(\frac{1.36 \times 10^9}{10^{-6}} \right)^{1/2} \times \frac{3.14}{4}(1 \times 10^{-3})^2$[/tex]

        = 28.96 A

Now considering the relation for the current flow through the finite potential difference.

[tex]$E=I_{max} \times R$[/tex]

[tex]$E=I_{max} \times \rho \times \frac{L}{A}$[/tex]

[tex]$L=\frac{AE}{I_{max} \ \rho}$[/tex]

[tex]$L=\frac{\frac{\pi}{4} \times (1 \times 10^{-3})^2 \times 110}{28.96 \times 10^{-6}}$[/tex]

   = 2.983 m

Now calculating the power rating of the heater:

[tex]$P= E \times I_{max}$[/tex]

[tex]$P= 110 \times 28.96}$[/tex]

   = 3185.6 W

   = 3.1856 kW

Answer:

a.

y[n] = x[n] x[n-1]  x[n+1]

(i) Memory-less - It is not memory-less because the given system is depend on past or future values.

(ii) Causal - It is non-casual because the present value of output depend on the future value of input.

(iii) Invertible - It is invertible and the inverse of the given system is [tex]\frac{1}{x[n] . x[n-1] x[n+1]}[/tex]

(iv) Stable - It is stable because for all the bounded input, output is bounded.

(v) Time invariant - It is not time invariant because the system is multiplying with a time varying function.

b.

y[n] = cos(x[n])

(i) Memory-less - It is memory-less because the given system is not depend on past or future values.

(ii) Causal - It is casual because the present value of output does not depend on the future value of input.

(iii) Invertible - It is not invertible because two or more than two input values can generate same output values .

For example - for x[n] = 0 , y[n] = cos(0) = 1

                       for x[n] = 2[tex]\pi[/tex] , y[n] = cos(2[tex]\pi[/tex]) = 1

(iv) Stable - It is stable because for all the bounded input, output is bounded.

(v) Time invariant - It is time invariant because the system is not multiplying with a time varying function.

To generate a FM signal using FM modulator passband block, we need to first generate the message signal of 10 Hz and the carrier frequency of 100 Hz. The FM modulator passband block is used to modulate the message signal onto the carrier signal.

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To generate an FM signal using an FM modulator passband block with a message signal of 10 Hz and a carrier frequency of 100 Hz, we can use the following steps:

Create the message signal with a frequency of 10 Hz and a maximum amplitude of 1 using a waveform generator.

Create the carrier signal with a frequency of 100 Hz and a maximum amplitude of 1 using a waveform generator.

Use an FM modulator passband block to modulate the carrier signal with the message signal. The modulation index should be set to a value that provides the desired frequency deviation.

The FM modulated signal can be expressed mathematically as:

s(t) = Ac * cos[2pifct + KfInt(m(t)*dt)]

where s(t) is the FM modulated signal, Ac is the carrier amplitude, fc is the carrier frequency, Kf is the frequency sensitivity of the modulator, and m(t) is the message signal.

Apply a low-pass filter to the modulated signal to remove any high-frequency components that may have been introduced during modulation.

To demodulate the FM signal using a PLL, we can use the following steps:

Create a reference signal with the same frequency as the carrier signal using a waveform generator.

Use a mixer to multiply the FM modulated signal by the reference signal.

Pass the output of the mixer through a low-pass filter to obtain the error signal.

Feed the error signal into a phase detector.

Use a voltage-controlled oscillator (VCO) to generate a signal with a frequency that is proportional to the error signal.

Use a loop filter to adjust the output of the phase detector to control the frequency of the VCO.

Use a buffer to amplify the output of the VCO to obtain the demodulated message signal.

The output of the buffer will be the demodulated message signal, which should be a replica of the original message signal.

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Answer:

shrinkae limit = 20.35%

shrinkage ratio = 1.45

Explanation:

1. to get the shrinkage limit we would first calculate the moisture content w.

w = (37-28)/28

= 9/28

= 0.3214

then the formula for shrinkage limit is

[tex][w-\frac{(V-Vd}{wd} ]*100[/tex]

w = 0.3214

V = 19.3

Vd = 16

Wd = 28

when we put these values into the formula:

[tex][0.3214-\frac{(19.3-16)}{28} ]*100\\[/tex]

= 20.35%

2. the shrinkage limit = Wd/V

= 28/19.3

= 1.45

In Java, when a class is derived from another class, a relationship is formed between them. This relationship is known as the inheritance relationship, where the derived class inherits properties and methods from the parent class.

When you create a new object of the child class, the constructor of the parent class is automatically called before the constructor of the child class is executed. This is because the child class needs to initialize all the properties that it inherited from the parent class.

Now, if you experiment with a simple derivation relationship between two classes and put println statements in constructors of both the parent and child classes, but do not explicitly call the constructor of the parent in the child classes, you will see that the parent class constructor is still called before the child class constructor. This is because it is done implicitly by Java.

Here is a sample program that demonstrates this:

```
class Parent {
 public Parent() {
   System.out.println("Parent constructor called");
 }
}

class Child extends Parent {
 public Child() {
   System.out.println("Child constructor called");
 }
}

public class Main {
 public static void main(String[] args) {
   Child childObj = new Child();
 }
}
```

If you run this program, you will see the output as:

```
Parent constructor called
Child constructor called
```

Now, if you change the child's constructor to explicitly call the constructor of the parent, you will see that the output remains the same. However, the parent constructor is called explicitly this time.

Here is the modified sample program:

```
class Parent {
 public Parent() {
   System.out.println("Parent constructor called");
 }
}

class Child extends Parent {
 public Child() {
   super();
   System.out.println("Child constructor called");
 }
}

public class Main {
 public static void main(String[] args) {
   Child childObj = new Child();
 }
}
```

If you run this program, you will still see the output as:

```
Parent constructor called
Child constructor called
```

But this time, the parent constructor is called explicitly using the `super()` keyword inside the child's constructor.

I hope this helps you understand the inheritance relationship and how constructors work in Java. Let me know if you have any more questions.

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the "Parent" constructor was specifically called from the "Child" constructor. This is such that each constructor can either call a constructor in the superclass (called "super()") or a constructor in the same class (called "this()").

```
class Parent {
   public Parent() {
       System.out.println("Parent constructor called");
   }
}

class Child extends Parent {
   public Child() {
       System.out.println("Child constructor called");
   }
}

public class Main {
   public static void main(String[] args) {
       Child c = new Child();
   }
}
```
In this program, we have two classes: `Parent` and `Child`. `Child` is a subclass of `Parent`, meaning it inherits all of `Parent`'s methods and fields.
In the `Parent` constructor, we simply print a message saying that the constructor was called. Similarly, in the `Child` constructor, we also print a message saying that the constructor was called.
In the `Main` class, we create an instance of `Child` by calling its constructor. Notice that we do not explicitly call the `Parent` constructor in the `Child` constructor.
If you run this program, you'll see the following output:
```
Parent constructor called
Child constructor called
```
This is because when we create a new `Child` object, the `Child` constructor is called first. Since the `Child` constructor does not explicitly call the `Parent` constructor, the `Parent` constructor is automatically called for us.
Now, let's change the `Child` constructor to explicitly call the `Parent` constructor:
```
class Child extends Parent {
   public Child() {
       super();
       System. out.println("Child constructor called");
   }
}
```
Notice that we added the `super()` statement, which calls the `Parent` constructor.
If you run this program now, you'll see the following output:
```
Parent constructor called
Child constructor called
```
The output is the same as before. However, this time, we explicitly called the `Parent` constructor in the `Child` constructor. This is because every constructor must call either another constructor in the same class (`this()`) or a constructor in the superclass (`super()`).

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To complete the ConvertToPennies function, include a conditional statement that checks if numPennies is provided and calculate the total pennies accordingly.


To complete the ConvertToPennies() function, follow these steps:
1. Add an 'if' statement to check if the 'numPennies' input is provided by using the 'nargin' function, which returns the number of function input arguments.
2. If 'numPennies' is provided (nargin == 2), calculate the total pennies by multiplying 'numDollars' by 100 and adding 'numPennies'.
3. If 'numPennies' is not provided (nargin == 1), calculate the total pennies by simply multiplying 'numDollars' by 100.
Here's the completed code:
function totalPennies = ConvertToPennies(numDollars, numPennies)
   % numDollars: Number of dollars
   % numPennies: Number of pennies (optional)
   % Function output: Total number of pennies
   if nargin == 2
       totalPennies = (numDollars * 100) + numPennies;
   else
       totalPennies = numDollars * 100;
   end
end

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Answer: the engineers are performing a tensile test

Explanation:

i took the test and got it right

Answer:

the answer. for this is Crankshaft

The wet unit weight is 106.5 lb/ft3, the dry unit weight is 97.3 lb/ft3, the porosity is 35.9%, and the degree of saturation is 23.3%.

To solve this problem, we need to use the following equations:

Void ratio (e) = Volume of voids (Vv) / Volume of solids (Vs)

Porosity (n) = Vv / Vt, where Vt is the total volume of the soil sample (Vt = Vv + Vs)

Degree of saturation (Sr) = (Vw / Vv) x 100, where Vw is the volume of water in the soil sample

Dry unit weight ([tex]γd[/tex]) = (Gs / (1 + e)) x [tex]γw[/tex], where Gs is the specific gravity of the soil and [tex]γw[/tex] is the unit weight of water (62.4 lb/ft3)

Wet unit weight [tex](γw[/tex]) = [tex]γd[/tex] + (w x [tex]γw[/tex]), where w is the water content of the soil sample

Given data:

Void ratio (e) = 0.56

Water content (w) = 15%

Specific gravity of soil (Gs) = 2.64

First, we need to calculate the dry unit weight:

[tex]γd[/tex] = (Gs / (1 + e)) x [tex]γw[/tex]

[tex]γd[/tex] = (2.64 / (1 + 0.56)) x 62.4

[tex]γd[/tex]= 97.3 lb/ft3

Next, we can calculate the wet unit weight:

[tex]γw[/tex] = [tex]γd[/tex] + (w x [tex]γw[/tex])

[tex]γw[/tex] = 97.3 + (0.15 x 62.4)

[tex]γw[/tex] = 106.5 lb/ft3

Now we can calculate the porosity:

n = Vv / Vt

n = e / (1 + e)

n = 0.56 / (1 + 0.56)

n = 0.359 or 35.9%

Finally, we can calculate the degree of saturation:

Sr = (Vw / Vv) x 100

Sr = (0.15 x Vt) / Vv

Sr = (0.15 x (Vv + Vs)) / Vv

Sr = (0.15 / (1 - n)) x 100

Sr = (0.15 / (1 - 0.359)) x 100

Sr = 23.3%

Therefore, the wet unit weight is 106.5 lb/ft3, the dry unit weight is 97.3 lb/ft3, the porosity is 35.9%, and the degree of saturation is 23.3%.

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Answer:

-2 and 6

Explanation:

Let "x" and "y" be 2 numbers.

The sum of the two numbers is 4. The mathematical expression is:

x + y = 4

y = 4 - x   [1]

The sum of their squares minus three times their product is 76. The mathematical expression is:

x² + y² - 3 x y = 76   [2]

If we substitute [1] in [2], we get:

x² + (4 - x)² - 3 x (4 - x) = 76

x² + 16 - 8 x + x² - 12 x + 3 x² = 76

5 x² - 20 x - 60 = 0

We apply the solving formula for second order equations and we get x₁ = 6 and x₂ = -2.

If we replace these x values in [1], we get:

y₁ = 4 - x₁ = 4 - 6 = -2

y₂ = 4 - x₂ = 4 - (-2) = 6

As a consequence, one of the numbers is 6 and the other is -2.