Answer:
18
Step-by-step explanation:
Multiply 20 by 0.90 (that is 90%)
18 is the answer
Hope this helps :)
![\boxed{y=6\sqrt{3}}](https://tex.z-dn.net/?f=%5Cboxed%7By%3D6%5Csqrt%7B3%7D%7D)
<h2>
Explanation:</h2>
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:
![\frac{x}{3}=\frac{12}{x} \\ \\ x^2=36 \\ \\ x=\sqrt{36} \\ \\ x=6](https://tex.z-dn.net/?f=%5Cfrac%7Bx%7D%7B3%7D%3D%5Cfrac%7B12%7D%7Bx%7D%20%5C%5C%20%5C%5C%20x%5E2%3D36%20%5C%5C%20%5C%5C%20x%3D%5Csqrt%7B36%7D%20%5C%5C%20%5C%5C%20x%3D6)
But our goal is to find y. Let's call w the height of the small triangle, then:
![w=\sqrt{6^2-3^2}=3\sqrt{3}](https://tex.z-dn.net/?f=w%3D%5Csqrt%7B6%5E2-3%5E2%7D%3D3%5Csqrt%7B3%7D)
Applying the concept of ratios again:
![\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}}](https://tex.z-dn.net/?f=%5Cfrac%7By%7D%7Bw%7D%3D%5Cfrac%7Bx%7D%7B3%7D%20%5C%5C%20%5C%5C%20y%3Dw%20%5Cleft%28%5Cfrac%7Bx%7D%7B3%7D%5Cright%29%20%5C%5C%20%5C%5C%20y%3D3%5Csqrt%7B3%7D%5Cleft%28%5Cfrac%7B6%7D%7B3%7D%5Cright%29%20%5C%5C%20%5C%5C%20%5Cboxed%7By%3D6%5Csqrt%7B3%7D%7D)
<h2>Learn more:</h2>
Right triangle: brainly.com/question/10684799
#LearnWithBrainly
Answer:
-1/12
Step-by-step explanation:
you jus gotta substract and jawnt uerme! i know you got dis wrong, dont bluff cutie...