Answer: Choice A. 1/64
Work Shown:
f(x) = 4^x
f(-3) = 4^(-3)
f(-3) = 1/(4^3) ... see note below
f(-3) = 1/64
Note: I'm using the rule that a^(-b) = 1/(a^b)
W=l-8
a=9
a=lw
9=(l-8)l
9=l²-8l
0=l²-8l-9
factor
0=(l-9)(l+1)
set to zero
l-9=0
l=9
l+1=0
l=-1, false length can't be negative
l=9
the length is 9 units long
I think for this one, B seems the most right :)