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Need help with number 32. Also would help if you could tell me why D is wrong. Thanks!

Need help with number 32. Also would help if you could tell me why D is wrong. Thanks-example-1
User Luhmann
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1 Answer

6 votes
So for surface area, imagine I was wrapping the object without overlapping. The area of the wrapping paper would be what we are trying to fine out.

Now the are of a triangle is:
A=(1/2)lh
l=length
h=height

The area of a square is:
A=lw
W=width

So for the total surface area, we have one square (the side on the bottom), and four triangles of the same size (the surrounding triangles).

So the total surface area would be
SA=l*w+4*((1/2)*l*h)
Now that we have the equation, we can substitute in the numbers for the variables.

SA=5*5+4*(1/2)*5*7

Now we can start simplifying the equation down.

SA=25+70
SA=95

Now add in the unit^2 and you're all set.

Answer: 95ft^2

Hope this helped!
User Paul Razvan Berg
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