### Home > PC > Chapter 10 > Lesson 10.1.3 > Problem10-43

10-43.

Draw and label a diagram.

See diagram at right.
What expression would you use for the '?' ?

Write a proportion using the similar triangles in the diagram.

$\frac{1.8}{20-\textit{d}}=\frac{\textit{h}}{20}$

Now rewrite the equation in h = form.