Answer:
x=-2, y=4, z=-3
Step-by-step explanation:
(1) -5x +3y +6z=4
(2) -3x + y + 5z=-5
(3) -4x + 2y + z= 13
(1)-(2)-(3)
-5x +3y +6z - (-3x + y + 5z) - (-4x + 2y + z) = 4-(-5)-13
-5x+3x+4x = 9-13
2x=-4
x=-2
put back in (2)
-3(-2) + y + 5z=-5
y + 5z = -11
multiply by 2
2y + 10z = -22
subtract from (3)
10z - (-4(-2) + z) = -22-13
9z - 8 = -35
9z=-27
z=-3
substitute x n z back in, y=4
