Find the lateral surface area of the figure.

A. 798 sq ft
B. 210 sq ft
C. 816.8 sq ft
D. 69.7 sq ft

Surface area of the cylinder = 816.4 sq. ft.

Solution:

Height of the cylinder = 21 ft

Diameter of the cylinder = 10 ft

Radius of the cylinder = 10 ÷ 2 = 5 ft

Use the value of = 3.14

Surface area of the cylinder =

Substitute the given values in the surface area formula, we get

Surface area of the cylinder

                                                ft²

Hence the surface area of the cylinder is 816.4 sq. ft.

or

step-by-step explanation:

we need to solve for 'x' the following equation:  

we have that:

⇒

⇒ ⇒

factorizing, we get that:

  ⇒

then, the solutions are: or

nothing extraneous has been found!