a terminal arm passes through the point (-4,15). In standard position, to the nearest degree, the measure of the principal angle is?

Question

anonymous · Answer

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You need to find the measure of x.
To do this, you need to plug the numbers into your calculator.
We know that the tan value is opposite over adjacent, so 15/-4. However, DO NOT put the negative into the calculator because we are finding a reference angle.
When you do this, you should get the angle to be approximately 75 degrees.

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Therefore, when you subtract the reference angle (75) you will get the measure of the angle (105)