6.2 Calculating with the tangent

With trigonometry we often need to write down which sides we are calculating or which sides we already have information of. There are names to the sides that help you calculate the angles or the length of the sides. The picture below shows you what we call these sides. The hypotenuse is always the longest side. Which side is adjacent or opposite depends on the angle you are using. 

 

Use the picture above for the following questions.

 

In paragraph 6.1 they explain how you can calculate the tangent of ∠A with the length of the opposite side and the length of the adjacent side. 

In paragraph 6.2 we learn that with the tangent of ∠A and either the length of the opposite side or the adjacent side, we can calculate the length of the other side. Always fill in the information you have in the following formula: