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This problem is an application of a system, solving a system of equations.
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In this problem, we are told there is a rectangular piece of cardboard that has an area of 216 square centimeters.
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This piece of cardboard is going to be rolled up to make a cylindrical tube by joining together two sides of the rectangle.
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And the tube is to have a volume of 224 cubic cubic.
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Centimeters and we're asked to find what size the cardboard should be.
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So in this problem, i'm going to start off and i'm going to let l be the length of the piece of cardboard and w the width.
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Well, we know that the area of a rectangle is length times width.
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So on this problem, the length times the width is 216 square centimeters.
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So we also know that the volume of the tube that we're going to make is going to be the volume of a cylinder, which is 2 times pi, times the radius squared, times the height of the cylinder.
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Okay, so we're going to try to put this together.
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Over on the first part of the problem, where we know that the length times the width is 216.
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And we're going to say this cylinder is going to be rolled up in this direction.
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Should be cardboard to make the cylinder.
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So the length is 216 divided by w...