Question

If f(x)=9-2|x + 21, find f(-7).

Answer 1

Answer: -1
Same thing as the other question that I helped you with:

Substitute -7 for x

f(-7) = 9-2|-7+2|

Treat the absolute value like parenthesis, and follow the rules of PEMDAS

9-2|-5|

9-2*5

9-10

-1