Question

Solve the system x+2y-5z=10, y+2z=2, z=-1

Answer 1

x=-3,y =4 z=-1

Explanation:

x+2y-5z=10

y+2z=2

z=-1

Since z = -1, substitute into the second equation

y + 2(-1)=2

y -2 =2

y = 2+2

y=4

We can substitute into the first equation

x+2(4) -5(-1) =10

x+8+5=10

x+13 = 10

x = 10-13

x=-3