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Need help with this problem its really complicated for me

Need help with this problem its really complicated for me-example-1
User Mikasa
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1 Answer

3 votes

You can write a proportion because the two triangles are similar


(x)/(x-2) =
(x + x + 5)/(x + 1 + x - 2) (the second fraction is longer because I added the full lengths of the larger triangle) cross multiply to get (x)(x + 1 + x - 2) = (x - 2)(x + x + 5)

which simplifies to (x)(2x - 1) = (x - 2)(2x + 5)

then 2x² - x = 2x² + 5x -4x - 10

then 2x² - x = 2x² + x - 10

then 2x² = 2x² + 2x - 10

subtract 2x² from both sides to get 0 = 2x - 10

add 10 to both sides to get 10 = 2x

divide both sides by 2 to get 5 = x

User ThingEvery
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