Question

The radius of a cylinder is 3x - 2 cm. The height of the cylinder is x + 3 cm. What is the surface area of the cylinder? Use the formula A = 2πr^2 + 2πrh.
A. 2π(3x^2 + 10x - 8)
B. 2π(12x^2 + 7x - 2)
C. 2π(12x^2 - 2x +13)
D. 2π(12x^2 - 5x -2)

Answer 1

Surface area = 2 pi (3x-2)^2 + 2 pi  (3x -2) ( x + 3)

= 2 pi (9x^2 - 12x + 4 + 3x^2 + 7x - 6

= 2pi(12x^2 - 5x - 2)

Its D