Respuesta :

Answer: 5

Step-by-step:

1. set up equations : 4x+12=8 and 2x+7=?

2. solve for x in the first eq.

4x + 12 = 8

4x = -4

x = -1

3. plug x = -1 into  2x+7=?

2 ( -1 ) + 7 =

-2 + 7 =

5