Geometry question

Question

A triangular prism has base edges 3 cm, 7cm, and 8cm long. It’s lateral area is 378 centimeters squared. What is the height of the prism

Answer 1

The only reason that this would seem hard would be if you didn't know what lateral faces are. These are the vertical faces, or faces perpendicular to the base. The area is the perimenter of the base times the height.

A = (3 + 7 + 8) h

A = 18h

378 = 18h

h = 21

21 cm