If angles are complementary, they add up to 90 whereas when they are supplementary, the add up to 180. So now let's focus on this problem. It says angle 1 and 2 are complementary. Therefore; angle 1 + angle 2 =90 x+(3x+30)=90 x+3x+30=90 4x+30=90 -30 -30 4x=60 4/4x=60/4 x=15 Therefore, the value of x is 15