Trigonometry · Radians and the unit circle

How to Convert Radians to Degrees

Problem

5π6\frac{5\pi}{6}

Answer

150∘150^\circ

Radians and degrees measure the same angles in different units. To go from radians to degrees, multiply by 180 over pi and cancel.

Step-by-step solution

  1. Multiply the radians by 180 over pi.

    5π6×180∘π\frac{5\pi}{6} \times \frac{180^\circ}{\pi}

    Why: A full turn is 2 pi radians or 360 degrees, so the factor between them is 180 over pi.

  2. Cancel pi and multiply.

    5×180∘6=900∘6\frac{5 \times 180^\circ}{6} = \frac{900^\circ}{6}

    Why: Pi appears on the top and the bottom, so it cancels.

  3. Divide to finish the conversion.

    900∘6=150∘\frac{900^\circ}{6} = 150^\circ

    Why: 900 divided by 6 is 150.

Common mistakes

  • Multiplying by pi over 180 instead of 180 over pi.
  • Keeping the radian label in the answer. The result is in degrees.
  • Cancelling pi but forgetting to divide by 6.

Practice problems

Use the same method. Work each problem on paper, then open the answer to check.

  1. π3\frac{\pi}{3}

    Show answer

    60∘60^\circ

  2. π4\frac{\pi}{4}

    Show answer

    45∘45^\circ

  3. 3π2\frac{3\pi}{2}

    Show answer

    270∘270^\circ

  4. 2π2\pi

    Show answer

    360∘360^\circ

  5. 7π6\frac{7\pi}{6}

    Show answer

    210∘210^\circ