Question

Solve the following system of equations.

x + 3y + 2z = –16
2x – y + 2z = –15
2x – 2y – z = 1

Answer 1

(2x – y + 2z) - (x + 3y + 2z) = -15 + 16
x - 4y = 1
x = 1+4y
(2x – 2y – z) - (2x – y + 2z) = 1 + 15
-y - 3z = 16
2(1+4y) - 2y - z = 2 + 6y - z = 1
6y - z = -1
18y - 3z = -3
-19y = 19, y = -1
x = -3
z = -5

--- (–3, –1, –5)