~~Start by getting all the factors of 36.
Factors of 36: 1x36, 2x18, 3x12, 4x9, 6x6. So there is 10 factors. So that means there are 10 different rectangles. That also means that there are 20 rectangles, an example is a rectangle’s width 1 and the length is 36. It can be the width is 36 and the length is 1.