# 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).

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