SOH CAH TOA is an acronym used to find missing sides and angles of right triangles (its not just a jumble of letters!)
Finding Missing Angles: When given 2 sides of a right triangle, we can find a missing angle. SOH CAH TOA tells us which function to use based on which sides were given (the side adjacent to the missing angle, opposite or hypotenuse). SOH CAH TOA gives us the ratio of the missing angle and the inverse function on our calculator turns that function into an angle measurement. Remember to make sure your mode is set to degrees not radians
Finding Missing Sides: If we know an angle and a side, we can find the other missing side by going in reverse. Figure out which function to use based on the side that you have and the side that you need to find in relation to the given angle. Then take the COS, SIN or TAN of that given angle (not the inverse! inverse takes ratios and turns them to angles. We need to take an angle and make it a ratio) and set it equal to the ratio of the known side and unknown side and solve for x.
Below is the powerpoint that we used in class to introduce SOH CAH TOA and the missing angles
Word problems take what you know about solving for missing angles and sides and turn it into real world application. To solve a lot of the SOH CAH TOA word problems, you need to understand Angles of elevation and depression. Below are 2 videos that re-explains what it is and goes through practice problem with you.
Please note the answer to the review #5 on the review below is incorrect. The angle of depression is not properly labeled. You should use Cos 57, as thats 90 degrees minus the angle of depression.