The line that is a linear model from the data is line c.
The formula for a diagonal of a rectangle is <span>√w^2+h^2, with w and h being the width and height. Plug in your numbers to get </span><span>√7^2+5.5^2. Simplify that into </span><span>√49+30.25, then to </span><span>√79.25. Use your calculator to get 8.9022. The diagonal is 8.9 feet.</span>
We will have to use proportions:

Cross multiplying we get

Now divide:

Solve to tenths place we get

The woman casts a 36.6 ft long shadow.