A=LW
P=2(L+W)
54=LW
30=2(L+W)
15=L+W
minus W both sides
15-W=L
sub 15-W for L
54=(15-W)W
54=15W-W^2
times -1 both sides
-54=W^2-15W
add 54 both sides
0=W^2-15W+54
factor
what 2 numbers multiply to get 54 and
add to get -15
-9 and -6
0=(W-9)(W-6)
set to zero
w-9=0
w=9
w-6=0
w=6
15-W=L
15-9=6
15-6=9
the dimentions are 6 inches by 8 inches
