Chapter 1 Activity 3
Activity 3a
The sum of the measures of the interior angles of an arbitrary triangle is 180 degrees.
Activity 3b
The sum of the measures of the interior angles of an arbitrary quadrilateral is 360 degrees.
Activity 3c
The two sums are related because if two triangles are placed together, they create a quadrilateral. So the sum of the two triangles (180) will equal a quadrilateral (360).