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$ ext{How to find reference angle not on unit circle}$

Answer 1

Abigail Nelson

Daniel Carter

Given an angle of 210 degrees, find the reference angle.

Step 1: Determine the quadrant in which the angle lies. 210 degrees is in the third quadrant.

Step 2: Use the formula for finding the reference angle in the third quadrant: $\theta_{ref} = \theta – 180^\circ$.

Step 3: Substitute the given angle into the formula: $\theta_{ref} = 210^\circ – 180^\circ$.

Step 4: Simplify: $\theta_{ref} = 30^\circ$.

Answer 2

Alex Thompson

Emma Johnson

Given an angle of 135 degrees, find the reference angle.

Step 1: Determine the quadrant in which the angle lies. 135 degrees is in the second quadrant.

Step 2: Use the formula for finding the reference angle in the second quadrant: $ heta_{ref} = 180^circ – heta$.

Step 3: Substitute the given angle into the formula: $ heta_{ref} = 180^circ – 135^circ$.

Step 4: Simplify: $ heta_{ref} = 45^circ$.

Answer 3

Amelia Mitchell

Maria Rodriguez

Given an angle of 300 degrees, find the reference angle.

Step 1: Determine the quadrant in which the angle lies. 300 degrees is in the fourth quadrant.

Step 2: Use the formula for finding the reference angle in the fourth quadrant: $ heta_{ref} = 360^circ – heta$.

Step 3: Substitute the given angle into the formula: $ heta_{ref} = 360^circ – 300^circ$.

Step 4: Simplify: $ heta_{ref} = 60^circ$.