# Find the radian measure of the angles of triangle ABC if angle A = 60 degrees, angle B = 45 degrees

Before finding the radian measure of the angles of triangle ABC, we first find out the degree measure of the angle C.

According to the rule, the sum of the values of all the angles of any triangle is 180 °.

Now we will write for ΔABC and calculate.

A + B + C = 180 °.

C + A + B = 180 °.

C + 60 ° + 45 ° = 180 °.

C + 105 ° = 180 °.

C = 180 ° – 105 °.

C = 75 °.

Next, we find the radian measure of all angles ΔABC.

According to the formula a ° = a × π / 180, where a ° is the degree measure of the angle, and π is an irrational number.

1.) Now we find the radian measure of the angle A.

60 ° = 60 × π / 180 = π / 3.

Most often, when calculating the measure of an angle in radians, the name “rad” is not indicated.

2.) Next, find the radian measure of the angle B.

45 ° = 45 × π / 180 = π / 4.

3.) Find the radian measure of the angle C.

75 ° = 75 × π / 180 = 5π / 12.

Answer: A = π / 3; B = π / 4; C = 5π / 12.