The length of a rectangle is four times its width. If the area is 100 m2 what is the length of the rectangle? Choose the correct answer.
A) 50 m
B) 40 m
C) 80 m
D) 20 m
E) 70 m
Let L be the length and W be the width of the rectangle. Hence   L = 4 W   We now use the area to write   100 = L ? W   Substitute L by 4 W in the equation above   100 = 4 W ? W = 4 W2   Solve for W and find L   4 W2 = 100   W2 = 25 , W = 5 and L = 4 W = 20 m   correct answer 20 m
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The length of a rectangle is four times its width. If the area is 100 m2 what is the length of the rectangle?