Answer:
<h2>Such triangles do not exist.</h2>
Step-by-step explanation:
There is some mistake in your question.
We know:
In any triangle with sides <em>a</em>, <em>b</em> and <em>c</em>:
<em>a + b > c</em>
<em>a + c > b</em>
<em>b + c > a</em>
In your question the triangle ABC has:
<em>a = 5, b = 10, c = 15</em>
then
<em>5 + 10 = 15 </em>not <em>> 15</em>.
<em>a + b = c</em> not <em>> c.</em>
<em></em>
<em>In my opinion, the question makes no mathematical sense.</em>
<em>Nevertheless, the moderator asked me to correct my answer.</em>
<em />
If two triangles are similar, then corresponding sides are in proportion.
![\dfrac{10}{5}=\dfrac{20}{10}=\dfrac{x}{15}\\\\2=2=\dfrac{x}{15}\\\\\dfrac{x}{15}=2\Rightarrow x=30](https://tex.z-dn.net/?f=%5Cdfrac%7B10%7D%7B5%7D%3D%5Cdfrac%7B20%7D%7B10%7D%3D%5Cdfrac%7Bx%7D%7B15%7D%5C%5C%5C%5C2%3D2%3D%5Cdfrac%7Bx%7D%7B15%7D%5C%5C%5C%5C%5Cdfrac%7Bx%7D%7B15%7D%3D2%5CRightarrow%20x%3D30)