Find the value of y.
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[tex]\boxed{y=6\sqrt{3}}[/tex]
For a better understanding of the problem I've built up two triangles from the given triangular shape. So these two triangles are similar. Therefore, we can solve this problem by using ratios and corresponding sides in this way:
[tex]\frac{x}{3}=\frac{12}{x} \\ \\ x^2=36 \\ \\ x=\sqrt{36} \\ \\ x=6[/tex]
But our goal is to find y. Let's call w the height of the small triangle, then:
[tex]w=\sqrt{6^2-3^2}=3\sqrt{3}[/tex]
Applying the concept of ratios again:
[tex]\frac{y}{w}=\frac{x}{3} \\ \\ y=w \left(\frac{x}{3}\right) \\ \\ y=3\sqrt{3}\left(\frac{6}{3}\right) \\ \\ \boxed{y=6\sqrt{3}}[/tex]
Right triangle: https://brainly.com/question/10684799
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