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Flapdragon
If a cylinder has a height that is 2 times as large as its radius, and the lateral area of the cylinder is 16pi square units, then what is the length of the radius of the cylinder?
Let radius = r units ==> ht = 2r units A = 2πrh 2πr(2r) = 16π 4r^2 = 16 r = 4 units