Question

I need help finding the lateral area and surface area of this cylinder but I have to leave π in my answer. Can anyone help?

Answer 1

The lateral surface of a cylinder can be found with the equation 

A = 2 π r h          Substitute in your values.
A = 2 π (11) (7)   Multiply 11 and 7.
A = 2 π (77)        Multiply 77 and 2.
A = 154π            Don't simplify anymore so you can keep pi in the answer.

The surface are uses the equation
 
A = 2 π r h + 2 π r²               Substitute in your values.
A = 2 π (11) (7) + 2 π (11)²   Simplify and multiply your terms.
A = 2 π (77) + 2 π (11)²
A = 154 π + 2 π (11)²
A = 154 π + 2 π (121)
A = 154 π + 242 π                Since both terms are in terms of pi, you can                                                 combine them.
A = 396π                              Stop simplifying to leave the answer in terms                                               of pi.