what-is-the-side-length-of-the-largest-equilateral-triangle

https://www.gregmat.com/problems/problem/what-is-the-side-length-of-the-largest-equilateral-triangle/

I have understood the solution. But wanted to know how the two triangles are similar?

what-is-the-side-length-of-the-largest-equilateral-triangle

https://www.gregmat.com/problems/problem/what-is-the-side-length-of-the-largest-equilateral-triangle/

I have understood the solution. But wanted to know how the two triangles are similar?

Which two triangles?

Sorry my bad. I have not mentioned the triangles. I was concerned with two

Later I understood. Just pythogaras therom. Thanks