Respuesta :

Replace a and b in the equation with their values given:

-0.5(7(-6)-12(-10)-(8.4(-10)-14(-6))

Multiply within the parentheses

-0.5(-42 + 120) -(-84 + 84)

Add inside the parenthesis:

-0.5(78)-0

Multiply:

-.05 x 78 = -39

The answer is -39