Question

Solve the following system of equations.

4x – 3y + z = –9
x + 2y + 2z = 5
x – 2y + 3z = –2

Answer 1

Choices:

(1, 1, –10)

(1, 2, –7)

(–1, 2, 1)

(–1, 1, 0)

Answer 2

Just solved it i think:

z = -9 - 4x + 3y
x + 2y + 2(-9 - 4x + 3y) = 5
x - 2y + 3(-9 - 4x + 3y) = -2

x + 2y - 18 - 8x + 6y = 5
x - 2y - 27 - 12x + 9y = -2

-7x + 8y = 23
-11x + 7y = 25
4x + y = -2
y = -2 - 4x

-7x + 8(-2 - 4x) = 23
-7x - 16 - 32x = 23
-39 x = 39
x = -1

y = -2 - 4x= 2

z = -9 - 4x + 3y = -9 + 4 + 6 = 1

(-1, 2, 1)