Find the unknown side A ( trigonometry with one known side and an angle)

  1. First we need to make sure we have a nicely labelled triangle, identifying which sides are the adjacent, opposite and hypotenuse. 2) Once these are labelled we will can work out which trig function to use with SOHCAHTOA 3) Now we can create an equation involving all off the information we know about the triangle eg COS(50)=A/104)Finally solve the equation to find the side length A ---- A=10COS(50)=9.65
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Answered by Tobias L. Maths tutor

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