Sum of all angles of triangle= 180 degrees
S is 3 times greater than angle R.
S= 3R
T is 12 degrees greater than R.
T= R+12
Now to find the measure of each angle,
Equation is:
3R+R+12+r=180°
5R+12=180°
5R=168°
R=33.6°
So, Angle R= 33.6°
Angle S= 3 x 33.6 = 100.8°
Angle T= 33.6+12=45.6°
Answer: Angle S=100.8° , Angle T=45.6° and Angle R=33.6°
