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Proportions in triangles. solve for x

Proportions in triangles. solve for x-example-1
User Harshit
by
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1 Answer

10 votes
x = 4



x / 3 = x + 4 / x + 2

Cross multiply
x * x + 2 = 3 * x + 4

Distribute
x^2 + 2x = 3x + 12

Set equal to zero
x^2 - x - 12 = 0

Factor
(x - 4)(x +3) = 0

Solve
x = 4 or x = -3

Length can’t be negative so x = 4

Check:
x / 3 = x + 4 / x + 2
4 / 3 = 4 + 4 / 4 + 2
4 / 3 = 8 / 6
4 / 3 = 4 / 3 :)
User Cosmologicon
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3.8k points