Question

What is the surface area of the prism?

Solid Figures, Part 1

A.
116 in2

B.
672 in2

C.
480 in2

D.
348 in2

Answer 1

To find the surface area of something, you need to find the area of all the sides and then add them together. The area formula of a rectangle is
\(\Large\tt\color{red}{Length \times Width}\)
The area formula of a triangle is
\(\Large\tt\color{blue}{Base \times height \div 2}\)

Answer 2

Do you want to do the triangles first or the recangles?

Answer 3

rectangles*

Answer 4

Either one is fine

Answer 5

Ok. I'll start with the triangles. Those triangles are both the same. Do you know what the base and height are?
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Answer 6

Actually, I don't know. I'm not very good with shapes.

Answer 7

The base is that bottom line. That would measure 16. The height is the dotted line that goes up the triangle. Notice how it goes through the center. It measures 6. So
\(\Large\tt\color{blue}{16 \times 6 \div 2}\)

Answer 8

What do you get when you finish that math?

Answer 9

48?

Answer 10

Yes. That's the area of one of the triangles. There are two of the same one. So either add
\[ 48 + 48\] or \[48\times2\]

Answer 11

96?

Answer 12

Yes. Remember that number. Now we can do the rectangles. We only need to multiply the length and the width. The length for a rectangle is kind of like the base of a triangle.
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Do you know the lenght and width of those ones?

Answer 13

.......Not really

Answer 14

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Those blue lines show the length and the width. The width is how tall the figure is. So what are the two numbers you should multiply if the blue lines are the length and width?

Answer 15

Sorry..

Answer 16

Those blue lines show the length and width so we multiply
\(\ 70 \times 10\)

Answer 17

10 and 7?

Answer 18

oops. yep, 7 and 10. Sorry lol

Answer 19

\(7 \times 10\)

Answer 20

It's okay don't be sorry

Answer 21

70

Answer 22

yep. There are two rectangles that look the same that both have an area of 70. So add 70+70 :)

Answer 23

140

Answer 24

yep. You'll need to remember that number, too. There's one last rectangle we need to find the area of.
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the red lines beside the blue lines show the length and width. So we multiply
\(16 \times 7\)

Answer 25

112

Answer 26

yes. So we add all of the areas we found. \[112+140+96\]

Answer 27

348

Answer 28

Yup :) So that's the surface area. \(348in^2\)

Answer 29

Thak you...So it's D?

Answer 30

*Thank

Answer 31

you got it

Answer 32

You're the best ;)