You can put this solution on YOUR website! Two Angles are Supplementary if they add up to 180 degrees
ley x,y be the supplementary angles
x+y=180.............eq(1)
an angle is 20 degrees less than thrice its supplement
x= 3*y-20
put x =3y-20 in x+y=180
(3y-20)+ y =180
3y+y-20=180
4y-20 = 180
move -20 to the right
4y =180+20
4y =200
divide with 4 on both sides
y =50
x= 3*50-20
=150-20
=130
so x=130
y= 50
ration x: y = 130:50
=13:5
Result : ratio =13:5