Please this is your answer.

8. -25

9. 8

Step-by-step explanation:

try following PEMDAS: Parentheses, Exponents, Multiplication and Division (from left to right), Addition and Subtraction (from left to right)

9. [12-10(2-1)+6]

12-10(1)+6

12-10+6

(12-10)+6

2+6

8

8. (8-2[3^2 +4]-7)

8-2[9+4]-7

8-2[13]-7

8-26-7

(8-26)-7

-18-7

-25

1/2

Step-by-step explanation:

18 inches is 1 1/2 ft

so 1/2 since it is half a yard