and your answer is -15x^4y
X=2
f(x)=4^2x-100
f(2)=4^2(2)-100
f(2)=4^4-100
f(2)=256-100
f(2)=156===> Answer
1. 4 3/4 feet = 19/4 feet
2 2/5 feet=12/5 feet.
multiplying them together yields


Part 2:
11.4 ft^2 - 4 1/2 ft^2=
11.4-4.5=6.9 ft^2 = 69/10 ft^2 left after you subtract the decoration in the middle
Now you're trying to find now many rectangular cutouts (that each are 3/8 ft^2) will fit in the remaining space.
You do that by dividing the remaining space left by 3/8:

since you have to have a whole number of cutouts, you round 92/5 down to 90/5, which is
18 cutouts