Question

Solve the system by substitution. 2x - y + z = -4 z = 5 -2x + 3y - z = -10

Answer 1

Substituting z = 5 into the first equation:

2x - y + 5 = -4
y = 2x + 9

Substituting y and z into the third equation
-2x + 3(2x + 9) - 5 = -10
4x + 27 = -5

x = -8
y = 2(-8) + 9 = 7
z = 5