<human>:  The length of a rectangle is four times its width. If the area is 100 m2. what is the length of the rectangle?
<bot>: Define a variable ** Let L be the length and W be the width of the rectangle.
How many meters is the length? ** Hence L = 4* W
How many meters is the area? ** We now use the area to write 80 = L * W
How many meters is the area? ** Substitute L by 4 W in the equation above 80 = 4*W × W = 4 W^2
How many meters is the length? ** Solve for W and find L
How many meters is the area? ** 4 W^2 = 100
How many meters is the width? ** W^2 = 25, W = 5 and
How many meters is the length? ** L = 4*5 = <<4*5=20>>20 m
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