In this video, we are going to learn about the proportions that exist when a perpendicular line is drawn from the right angle of a right triangle to the hypotenuse. The result is the formation of two smaller, similar right triangles.

Here, we have a large right triangle. After drawing a perpendicular line straight down to the hypotenuse from the right angle, it forms two smaller right triangles. These 3 right triangles are all similar, meaning that corresponding parts are in proportion to each other.

As shown in the video, we will label the different sides as *a* (leg 1), *b *(leg 2), *c *(hypotenuse), *h* (altitude), *x* (projection 1), and *y* (projection 2). Based on this diagram there are a few proportions that should be remembered:

*Note that if we are missing sides when trying to solve for these proportions, we can always use the Pythagorean Theorem to find the missing sides.

*Remember the following statement: The product of the means is equal to the product of the extremes. This applies to all three proportions listed above.