Respuesta :

lightswitch
Work:
Multiply a and 7
Multiply a and 1
The a just gets copied along.
7*a evaluates to 7a
8+7*a evaluates to 8+7a
8 + 4 = 12 which goes to 12+7a
(8+7*a)+4 evaluates to 12+7a

***The final answer is 12+7a***
8+7a+4
7a+12 is the simplified answer.