Final answer:
To determine the measure of angle R, we use the sum of angles in a triangle, which is 180 degrees. By setting up an equation with the given expressions for the angles and solving for x, we find angle R measures 69 degrees.
Step-by-step explanation:
To find the measure of angle R in triangle RST, we can use the fact that the sum of the angles in any triangle is 180 degrees. We are given:
- m R = (5x-11)°
- m S = (3x-3)°
- m T = (3x+18)°
Combining these equations, we get:
(5x - 11)° + (3x - 3)° + (3x + 18)° = 180°
Adding the equations gives:
11x + 4 = 180
Solving for x, we get:
x = 16
Substituting x back into the expression for m R:
m R = (5(16) - 11)° = 69°
Therefore, the measure of angle R is 69 degrees.