I really liked this angle matching task that I ran across in *Mathematics for the College Boards* by Rich Barnett (Copyright 1967 AMSCO).

If you follow this link, you can “borrow” the book for free as part of the Internet Archive’s Online Free Library.

There was a bit of confusion when I posted this question to twitter. The angles marked with an arc are not indicating that the angles are the same size. Instead, the arcs are there to indicate which angles we are finding the sum of in each diagram.

A commenter on twitter said that this type of question used to be standard fare on the SAT in the 1970s and 1980s.

## More Geometry Teaching Resources

- Right Triangle Trig Formula Sheet
- Pythagorean Theorem and Distance Formula Notes
- Pythagorean Theorem Day Celebration Ideas
- 25 Fun Geometry Puzzles
- Missing Angles Notes
- Classifying Triangles by Angles and Sides Notes
- Sankaku Puzzles
- Tricky Triangles Puzzle
- Triangular Turkey Puzzle
- Three of Five Puzzle
- SOH CAH TOA Notes
- Let’s Make Squares Activity