Question

Which of the following is the surface area of the right cylinder below? Will give medal and become fan!!(:

Answer 1

@ETG311 @JA1 @Candy13106

Answer 2

@ETG311

Answer 3

(h is the height of the cylinder, r is the radius of the top)

Surface Area = Areas of top and bottom +Area of the side

Surface Area = 2(Area of top) + (perimeter of top)* height

Surface Area = 2(pi r 2) + (2 pi r)* h

In words, the easiest way is to think of a can. The surface area is the areas of all the parts needed to cover the can. That's the top, the bottom, and the paper label that wraps around the middle.

You can find the area of the top (or the bottom). That's the formula for area of a circle (pi r2). Since there is both a top and a bottom, that gets multiplied by two.

The side is like the label of the can. If you peel it off and lay it flat it will be a rectangle. The area of a rectangle is the product of the two sides. One side is the height of the can, the other side is the perimeter of the circle, since the label wraps once around the can. So the area of the rectangle is (2 pi r)* h.

Add those two parts together and you have the formula for the surface area of a cylinder.

Surface Area = 2(pi r 2) + (2 pi r)* h

Answer 4

@Candy13106

Answer 5

2 pi r 2 + 2 pi r h

Answer 6

so wahts the radius i cant see to well :/

Answer 7

I got it bvmind! (: I got 126 (:

Answer 8

what he said(:

Answer 9

*nevermind

Answer 10

sorry i was busy at the time and didnt see your question!

Answer 11

ok lol

Answer 12

it's okay! the pics will be clearer now (: Next question comming up!

Answer 13

k :D