What is the radius of a base cylinder that has a surface area of 100.5 square inches and height is 6 inches?

If it is a right circular cylinder,then

A = 2pir2 + 2pirh

2pir2 + 2pirh = A

2pir2 + 2pir*6 = 100.5 divide both sides by 2pi

r2 + 6r = 50.25/pi form the square

r2 + 6r + 9 = 9 + 50.25/pi

(r + 3)2 = 9 + 50.25/pi

r + 3 = √(9 + 50.25/pi) since 32 < 9 + 50.25/pi

r = -3 + √9 + 50.25/pi

r ≈ 2 in

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