what is the Width and what is the Height

Question

A bookcase is to have 4 shelves including the top as pictured below.

The width is to be 24 feet less than 4 times the height. Find the width and the height if the carpenter expects to use 30 feet of lumber to make it.

Answer 1

h represents the height

4h - 24 represents the width

2h + 4(4h - 24) = 30

Can you solve for h and answer?