Question

Solve the system by back substitution.- 4x - 8y - 22 - 6w = 4y +62 + 2w = 8Z + W = 25w = 15The solution set is ? (Type an integer or a simplified fraction.)

Answer 1

Solve the system by back substitution.

- 4x - 8y - 22 - 6w = 4 (I)

y +62 + 2w = 8 (II)

Z + W = 2 (III)

5w = 15 (IV)

We'll start by equation (IV):

5w=15

w=3

Now, (III):

z+w=2

z+3=2

z=-1

Now, we follow to (II)

y+62+2w=8

y+62+6=8

y=8-68

y=-60

FInally, equation (I):

-4x-8*(-60)-22-6*3=4

-4x +480-22-18=4

-4x=4-440

-4x=-436

x=109

The solution set is: S={109, -60, -1, 3}