### Home > AC > Chapter 16 > Lesson 16.9.2.2 > 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 100 meters. Homework Help ✎ Label all sides.

Find

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

*x*.

2*y* + 3*x* = 100

2*y* = 100 − 3*x*

Area_{total} = Area_{rectangle} + Area_{triangle}

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