# Week 17 – Angles in Standard Position

This week I learned about angles in standard position.

Here is a common question:

This question first asked me to graph point P in standard position. I did this by using the x value 11 and y value -7, and then connected the lines to create a right triangle. The next question asked me to determine the primary trigonometric ratios of theta, so then I had to find the missing side length r by using pythagoras theorem. After I had all the side lengths of the triangle I could plug them into sin y/r cos x/r and tan y/x. The last question asked me to figure out what theta was. First I used tan to get the reference angle, and then I subtracted 360° to get the rotation angle.

This week we also learned the sine law and the cosine law. You can use the sine law when you have an angle that is across from a side length. For the sine law you also have to use the cast rule to figure out if there is an ambiguous angle. You can use the cosine law when you have two side length and one angle or all three side lengths.