Find the height of the triangle by applying formulas for the area of a triangle and your knowledge about triangles. this is a triangle. side a has a length of 15 cm. side b has a length of 20 cm. side c has a length of 25 cm. the altitude to side c has a length of x cm. a. 8.5 cm b. 10.5 cm c. 12 cm d. 3.4 cm