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I need to solve this practice exercise by the process of elimination. I am unsure of how to proceed.

I need to solve this practice exercise by the process of elimination. I am unsure-example-1

1 Answer

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Answer:

The solution to the system of equation is:

x = -2

y = -1

z = -1

Step-by-step explanation:

Given the system of equations:

4x - 3y - 6z = 1 .............................................(1)

x - y - 6z = 5 .................................................(2)

6x - y = -11 .....................................................(3)

Subtract (2) from (1) to eliminate z

3x - 2y = -4 ...................................................(4)

Multiply (4) by 2 and subtract (3) from the result to eliminate x

(4) * 2: 6x - 4y = -8

- (3)

-3y = 3

Divide both sides by -3

y = 3/(-3) = -1 ......................................................(5)

Multiply (3) by 2 and subtract (4) from the result to eliminate y

(3) * 2: 12x - 2y = -22

- (4)

9x = -18

Divide both sides by 9

x = -18/9 = -2 ........................................................(6)

Put x = -2 and y = -1 in (2) to find z

-2 - (-1) - 6z = 5

-1 - 6z = 5

-6z = 5 + 1

-6z = 6

Divide both sides by -6

z = 6/(-6) = -1 .........................................................(7)

Therefore, x = -2, y = -1, and z = -1(

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