Question 258781
Total perimeter will be 80+B=p
2L+2B=p
80+B=2L+2B
80=2L+B
if b=50 then
80=2L+50
30=2L
L=15
A=50*15=750
if b=30 then 
80=2L+30
50=2L
25=L
A=30*25=750
So A peaked at B=2*(50-30)=40

80=40+20+20
b=40

80+40=120
40+(40+20+20)
sides 40 and 20
40*20=800
maximum area 800 sq ft
40*20