The degrees on a triangle add up to 180.
(x) + (x-7) + (3x+12) = 180 ; Just shwoing what i'm doing.
x + x-7 + 3x + 12 = 180
5x + 5 = 180 ; x + x + 3x = 5x , 12 - 7 = 5
5x = 175 ; Subtract 5 from 180
x = 35 ; 175/5 = 35
x=35
P: x - 7 = 35 - 7 = 28
Q: 3 (x) + 12 = 3 (35) + 12 = 105 + 12 = 117
R: x = 35
P= 28 degrees, Q= 117 degrees, R= 35 degrees.
