Proving that two polygons have the same area can be as easy as cutting them up and rearranging the pieces. Gina the geometry student stayed up too late last night doing her homework while watching The ...

A square has four right angles (90°). Each diagonal splits a corner into two angles of 45°. Note also that the diagonals cut each other in half at right angles. A rectangle has four right angles. The ...

Construct a convex octagon with four right angles. It probably says a lot about me as a teacher that I assign problems like this. I watch as students try to arrange the right angles consecutively.

Click to see a step-by-step guide. STEP 1: Use the ruler to draw a diagonal line from the bottom right corner of the paper to the top left corner. Mark the 90° right angles in the bottom left and top ...