#### Apples+Pears^2

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- Thread starter Apples+Pears^2
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This is a system of equations; in fact, they are linear equations, so you have probably learned a couple ways to solve it. Try substitution.3x = 7y

x + y = 20

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There is a theorem that justifies this step.Why did you set up proportions? These triangles are not similar so I don't see how proportions apply to those sides.

And the picture is very inaccurate; to scale, it looks more like this:

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Oh ok that makes sense. I got the answer now. Thank you everyone!

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The perimeter is 30, so the sum of the unknown sides has to be 20. They have to be in the ratio 3:7. Since 3+7 = 10, we just have to double everything.

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OHHHHH~ I see how that works now.

The perimeter is 30, so the sum of the unknown sides has to be 20. They have to be in the ratio 3:7. Since 3+7 = 10, we just have to double everything.

For MN I got 6 and MO I got 14. And it works, since 6 is double of 3 and 14 is double of 7 and all the sides added together for perimeter is 30.

Thank you! =)