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Set up and solve a proportion to find the value of X.​

Set up and solve a proportion to find the value of X.​-example-1

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Answer: x = 1, 15

Explanation:

It is given that these triangles are similar, which means their corresponding side lengths will be proportional. Using this information, we can set up a proportion.


\displaystyle (2x-3)/(x-3)=(3x)/(x+5)

Next, we can cross-multiply. We will foil the left side and distribute the 3x in the right side.

(2x - 3) * (x + 5) = (3x) * (x - 3)

2x² + 7x - 15 = 3x² - 9x

Now, we will solve the x-variable. To do this, we will subtract (3x² - 9x) from both sides of the equation.

2x² - 3x² + 7x + 9x - 15 = 0

Combine like terms.

-x² + 16x - 15 = 0

Factor out a -1. Then, divide both sides of the equation by -1.

-1(x² - 16x + 15) = 0

x² - 16x + 15 = 0

Factor into two two-term polynomials.

x² - 16x + 15 = 0

(x - 1)(x + 15) = 0

Solve with the zero product property.

x = 1, 15

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