Khan Academy: Find Angles in Triangles

This short video show viewers how to connect the sum of the angles in a triangle to other angle measurements. Pupils determine the missing measures for angles involved with triangles and quadrilaterals. Class members then must explain...

Practice finding angle measures between intersecting lines.

A trigonometric ratio is a ratio between two sides of a right triangle. In this problem, find sin(A) in the given right triangle. Use the ratio of the opposite side over the hypotenuse.

Explains how to measure an angle in degrees using a protractor. Defines acute, right, and obtuse angles. Practice problems available. [8:22]

Use your knowledge of angles to find missing angle measures in various complex situations. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video, or receive hints.

Are you working on finding the missing angles in triangles in your class? Consider this video. An instructor uses the triangle sum theorem to create an equation that helps her find the missing angles. She explains each step and writes...

Use your knowledge about angles to find missing angle measures in various situations. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.

What's a trigonometric ratio? It is a ratio between two sides of a right triangle. In this problem, find tangent(A) in the given right triangle. Use the ratio of the opposite side divided by the adjacent side to find tan(A). The...

Using what we know to solve for angles in the Angle Game.

Are you working on finding the missing angles of triangles in your class? Consider this video. An instructor uses the triangle sum theorem to create an equation that helps her find the missing angles. She explains each step and writes...