Do Now: Quadrilateral Angles
Move the points A, B, C, and D in the quadrilateral below. Pay attention to the sum of all the angles.
Then, answer the questions that follow.
Besides the angles of a quadrilateral, what else do we know must sum to 360 degrees?
We know that the angles of a triangle sum to 180 degrees. How can we use this fact to show that the angles in a quadrilateral sum to 360 degrees?