### Home > PC > Chapter 9 > Lesson 9.2.2 > Problem 9-87

9-87.

A farmer with an eye for the unusual has decided to build a pentagonal enclosure whose shape will be a rectangle with an equilateral triangle sitting on top of it. (See figure at right.) The perimeter is

Label all sides.

Find

*y*in terms of.Find the area of the figure as a function of

.To find the area of the triangle, drop an altitude forming two congruent triangles. The diagonal will be '

'.Use the Pythagorean Theorem to find the height. The area will be

.