# geometry

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I have a question: My textbook says "The surface of a right prism is 224 sq. feet, and the length of a side of the square base is one-third the height. What are the dimensions of the prism?" How do I find out the dimensions when I don't know the height or the length of the sides? Please help. I have been working like crazy.

• geometry -

surface area = 2x^2 + 4xh

where x is the length of the side and h is the height.

let x= 1/3h

Then 224 = (2/9)h^2 + (4/3)h^2

solve it h = 12

then x = 1/3 h = 4

So the length is 4 and height is 12

• geometry -

4/3

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