Let $ABC$ be a triangle and $h_a,h_b,h_c$ the length of the heights.
(a) Find similar triangles at which it holds that $ah_a=bh_b$.
(b) Use (a) to show : Is $A'B'C'$ a second triangle and $h_a,h_b,h_c$ are again the length of the heights of this triangle, so these triangles are congruent.
For (a) do we have to give two specific triangles, i.e. give the negth of the sides? Or what exactly is asked?