<h3>
Answer: 30 feet</h3>
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Explanation:
He has 90 feet of fencing overall. This is the perimeter of the rectangle as its the distance around all four sides.
Two of the opposite sides are the width = 15 ft. So we have 15+15 = 30 feet taken up and 90-30 = 60 feet left for the other two opposite sides to add to. Call each of those sides x
x+x = 60
2x = 60
x = 60/2
x = 30
The other side must be 30 feet long.
This rectangle is 30 by 15
perimeter = 30+15+30+15 = 45 + 45 = 90
which helps confirm we have the right answer
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Or you can solve this way
P = 2*(L+W) is the perimeter of a rectangle with length L and width W
Plug in the perimeter P = 90 and the width W = 15. Solve for L
P = 2*(L+W)
90 = 2*(L+15)
2(L+15) = 90
L+15 = 90/2
L+15 = 45
L = 45-15
L = 30
Him doing the surgerys / treating the patient
