Answer:
length = 18 ft
Step-by-step explanation:
Let w = width
L = w+7
Area = l*w
198 = (w+7) (w)
Distribute
198 = w^2 +7w
Subtract 198 from each side
0 = w^2 +7w -198
Factor
What 2 numbers multiply to -198 and add to 7
18* -11 = -198
18+-11 = 7
0=(w+18) (w-11)
Using the zero product property
w+18 =0 w-11=0
w= -18 w=11
We cannot have negative width so w=11
We want the length
l = w+7
l = 11+7 = 18
