A rectangle has an area of 36 square feet. The width is five feet less than the length. What is the length of the rectangle?

Question

academicgurusinc · Answer

Define the rectangle where width = W and length= L

Area of rectangle = L*W=36

w= L-5 Substituted this equation for W above.  That is

L*W = 36
L* (L-5) = 36
L^2 - 5L = 36
L^2 - 5L - 36 = 0
Factor this:

(L-9)(L+4)=0

Thefore L= 9 or -4

Since the length cannot be a negative value, L must be 9 feet.

This is true because:

w= L-5= 9-5= 4
L= 9
Area=L*W = 
    =9*4
    =36

We hope this helps.


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Academic GurusInc.

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