Interior and Exterior Angle Sums
- Author:
- Sarah Stefaniak, Tim Brzezinski
- Topic:
- Angles
Use the picture below to answer the question on the piece of paper given to you.
Figure 1: Use the triangle below to answer the two questions under "Triangle Angle Sum Investigation".
FIGURE 2
Task 1
In figure 2, draw as many line segments as you can from point A to the other vertices, without tracing over a line that is already there. How many triangles did you break the shape into? Record this in your table.
Task 2
If the sum of the angles in each triangle is 180 degrees, how many degrees are in the sum of the quadrilateral in figure 2? Record this in your table.
FIGURE 3
Task 3
In figure 3, draw as many line segments as you can from point A to the other vertices, without tracing over a line that is already there. How many triangles did you break the shape into? Record this in your table.
Task 4
If the sum of the angles in each triangle is 180 degrees, how many degrees are in the sum of the pentagon in figure 3? Record this in your table.
FIGURE 4
Task 5
In figure 4, draw as many line segments as you can from point A to the other vertices, without tracing over a line that is already there. How many triangles did you break the shape into? Record this in your table.
Task 6
If the sum of the angles in each triangle is 180 degrees, how many degrees are in the sum of the hexagon in figure 4? Record this in your table.
FIGURE 5
Task 7
In figure 5, draw as many line segments as you can from point A to the other vertices, without tracing over a line that is already there. How many triangles did you break the shape into? Record this in your table.
Task 8
If the sum of the angles in each triangle is 180 degrees, how many degrees are in the sum of the heptagon in figure 6? Record this in your table.
Task 9
Complete the last row on your table without using a picture of the octagon based on your previous observations.