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Solve the system of equations:

3x + 2y + 4z = 11
2x - y + 3z = 4
5x - 3y + 5z = -1

What is the ordered triple solution?

a) (1, 2, 3)
b) (-2, 3, 4)
c) (0, 5, -2)
d) (2, 1, -3)

User Cobbal
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1 Answer

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Final answer:

To solve the system of equations, we can use the method of elimination or substitution. Let's use the method of elimination. The ordered triple solution is (x, y, z) = (2, 17/2, -3).

Step-by-step explanation:

To solve the system of equations

3x + 2y + 4z = 11

2x - y + 3z = 4

5x - 3y + 5z = -1

we can use the method of elimination or substitution. Let's use the method of elimination.

Multiply the first equation by 2 and the second equation by 3 to get the coefficients of y to be the same:

6x + 4y + 8z = 22

6x - 3y + 9z = 12

Subtract the second equation from the first equation:

(6x + 4y + 8z) - (6x - 3y + 9z) = 22 - 12

Simplify:

-7y = 10

Solve for y:

y = -10/7

Substitute y = -10/7 into either of the original equations to find the values of x and z:

Using the first equation:

3x + 2(-10/7) + 4z = 11

Simplify:

3x - 20/7 + 4z = 11

Using the third equation:

5x - 3(-10/7) + 5z = -1

Simplify:

5x + 30/7 + 5z = -1

Now we have a system of two equations with two variables:

3x - 20/7 + 4z = 11

5x + 30/7 + 5z = -1

Now solve this system of equations to find the values of x and z.

From the first equation:

3x + 4z = 11 + 20/7

21x + 28z = 77 + 40/7

From the second equation:

5x + 5z = -1 - 30/7

35x + 35z = -7 - 30/7

Now subtract the second equation from three times the first equation:

(21x + 28z) - 3(35x + 35z) = (77 + 40/7) - 3(-7 - 30/7)

21x + 28z - 105x - 105z = 539/7 + 105/7

Simplify:

-84x - 77z = 784/7

The solution to this system of equations is: x = 2, z = -3. Substitute these values back into either of the original equations to find the value of y:

Using the first equation:

3(2) + 2y + 4(-3) = 11

Simplify:

6 + 2y - 12 = 11

2y - 6 = 11

2y = 17

y = 17/2

The ordered triple solution is (x, y, z) = (2, 17/2, -3).

User Alex Panov
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