Question

-4x+y=3 and 2x-y=12. which of the options represents the resulting equation after an equivalent expression for yw is substituted into the second equation. Odessyware!

Answer 1

2x - (3 + 4x) = 12

x = -7.5

y = -27

Explanation:

-4x + y = 3 (1)

2x - y = 12 (2)

From (1)

y = 3 + 4x

Substitute y = 3 + 4x into (2)

2x - y = 12 (2)

2x - (3 + 4x) = 12

2x - 3 - 4x = 12

2x - 4x = 12 + 3

-2x = 15

x = 15/-2

x = -7.5

Substitute x = -7.5 into (2)

2x - y = 12 (2)

2(-7.5) - y = 12

-15 - y = 12

-y = 12 + 15

- y = 27

y = -27