The surface area of a rectangular prism is 190 square inches, the length is 10 inches, and the width 3 inches. Find the height.

I know how to do SA but I don't understand how to find height if you have SA given. The answer is 5 in but I am not able to come up with the right answer.

1 answer

Let x = height.

2(10*3) + 2(3x) + 2(10x) = 190

Solve for x.