Let L be the length and W be the width of the rectangle.
Hence L = 4* W
We now use the area to write 80 = L * W
Substitute L by 4 W in the equation above 80 = 4*W × W = 4 W^2
Solve for W and find L
4 W^2 = 100
W^2 = 25, W = 5 and
L = 4*5 = <<4*5=20>>20 m
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