Answer:
16m
Step-by-step explanation:
AB would be double DE
Solution:
f(x) = 7(9 - x) - 4
f(-1) = 7(9 - (-1)) - 4
f(-1) = 7(10) - 4
f(-1) = 70 - 4
f(-1) = 66
Best of Luck~
7.5^2
56.25