Question

ERROR ANALYSIS Describe and correct the error in solving for one of the variables in the linear system

8x + 2y = -12 and 5x - y = 4.

Answer 1

{x,y} = {-2/9,-46/9}

Hope it's right ;)

Explanation:

Answer 2

x =
`(2)/(9)` and y =
`-2(8)/(9)`

Explanation:

Given:

8x + 2y = -12

5x - y = 4

make y the subject in equation 2:

5x - y = 4

-y = 4 - 5x

y = 5x - 4

insert [ 5x - 4 ] as y in equation 2:

8x + 2y = -12

8x + 2(5x - 4) = -12

8x + 10x - 8 = -12

18x - 8 = -12

18x = -4

x =
`(2)/(9)`

solve for y:

y = 5x - 4

y = 5(
`(2)/(9)` ) - 4

y =
`(-26)/(9)` ____in improper fraction or
`-2(8)/(9)` ____in mixed fraction