From the question, I assume that:
- Two sides of a triangle are given
- The two triangles are corresponding to each other.
- 8 cm = 12 cm
- 10 cm = x cm
Place a similarity ratio:
Cross multiply and solve:
8 · x = 12 · 10
8x = 120
x = 120 ÷ 8
x = 15
The height of the triangle corresponding to 10 cm is 15 cm.