Not only are right triangles cool in their own right (pun intended), they are the basis of very important ideas in analytic geometry (the distance between two points in space) and …

Learn how to use trig functions to find an unknown side length in a right triangle.

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What is the law of sines? The law of sines is a formula that can be used to solve any triangles, not just right triangles. The law of sines states that in any triangle, the ratio of the sine of an angle …

Using what we know about 30-60-90 triangles to solve what at first seems to be a challenging problem. Created by Sal Khan.

In this unit, you will discover how to apply the sine, cosine, and tangent ratios, along with the laws of sines and cosines, to find all of the side lengths and all of the angle measures in any …

Say you had a question with an upright right triangle, angles ∠ A ∠B and∠ C with the right angle at A. You know both the angle measures of b and c, and you're using cos.

Learn how to find the sine, cosine, and tangent of angles in right triangles. The ratios of the sides of a right triangle are called trigonometric ratios. Three common trigonometric ratios are the …

Learn about arcsine, arccosine, and arctangent, and how they can be used to solve for a missing angle in right triangles.

Learn what it means for two figures to be similar, and how to determine whether two figures are similar or not. Use this concept to prove geometric theorems and solve some problems with …