1. How can I use a protractor to measure the size of an angle bigger than 180 degrees?


2. Why do the inside angles of a triangle always add up to 180 degrees?

Think of a triangle as being half of a rectangle.

The inside angles of a rectangle add up to 4 x 90 degrees = 360 degrees. Therefore for a triangle the inside angles will add up to half of this = 180 degrees.

3. Are congruent angles and equal angles the same thing?

A pair of congruent angles are the same size and a pair of equal angles are the same size.