The sum of the base and height of a triangle is 192 inches. The height is twice the base. Find the base and height of the triangle.

Representation of the unknowns is important here. Let the base be b and the height be h.

Then b + h = 192 inches. Also, h = 2b.

Then b + 2b = 192 inches, and 3b = 192 inches, so that b = 64 inches. The height is twice that: h = 128 inches.