Okay so first, area is length times width, so 1/4x*x would be first = 1/4(x^2)=64. Then area or x = 16 or -16
perimeter would be width times two plus length times two. I recommend using math papa to calculate these numbers.
thats the answer just look at the picture :)
for the work
<span> (3 + 1/4 u^4 − 2/3 u^9) du</span>