Think back to Task 1 of these Lesson Activities. Finding the area of a polygon using only coordinates can be tedious. Fortunately, you do have access to additional tools that help you find the area of a polygon while following the same basic methods. This is especially helpful when polygons are irregular or have many sides.

Next you will use GeoGebra to find the area of a polygon divided into a set of triangles. Go to area of a polygon, and complete each step below:

Partition the polygon into triangles by drawing line segments between vertices.
For each triangle, draw an altitude to represent the height of the triangle. Place a point at the intersection of the height and the base of each triangle.
Use the tools in GeoGebra to find the length of the base and the height of each triangle. (Because the values displayed by GeoGebra are rounded, your result will be approximate.)
Compute the area of each triangle, and record the results below. Show your work.
Add the areas of the triangles to determine the area of the original polygon, and note your answer below.