For the figure shown on the right, find the value of the variable and the measures of the angles.

Step-by-step explanation:
x-7+3x+12+x = 180
5x+5=180
5x=175
x = 35°
m L P = x-7 = 35-7 = 28°
m L Q = 3x+12 = 3(35)+12 = 105+12 = 117°
m L R = x = 35°