All SAT II Math II Resources
Example Question #1 : Finding Angles With Trigonometry
Evaluate to the nearest degree.
The figure referenced is below:
By the Law of Cosines, the relationship of the measure of an angle of a triangle and the three side lengths , , and , the sidelength opposite the aforementioned angle, is as follows:
All three side lengths are known, so we are solving for . Setting
, the length of the side opposite the unknown angle;
We get the equation
Solving for :
Taking the inverse cosine:
the correct response.