Use back-substitution to solve.

x = -16, y = -10, z = 7

Step-by-step explanation:

z = 7

y+2z = 4

Substitute z=7

y +2(7) = 4

y +14=4

Subtract 14

y +14-14 = 4-14

y = -10

x-y+5z = 29

Substitute z=7 and y = -10

x - (-10) + 5(7) = 29

x+10 +35 = 29

x +45 = 29

Subtract 45

x = 29-45

x =-16

it would be 6xy and -16xy.