SOLUTION: Please help me finish this problem. Angles DAY and MON are supplementary angles. If m∠DAY is 20 less than four times m∠MON, find m∠DAY Equation: m∠DAY

Algebra ->  Angles -> SOLUTION: Please help me finish this problem. Angles DAY and MON are supplementary angles. If m∠DAY is 20 less than four times m∠MON, find m∠DAY Equation: m∠DAY      Log On


   

Question 1055575: Please help me finish this problem.
Angles DAY and MON are supplementary angles. If m∠DAY is 20 less than four times m∠MON, find m∠DAY
Equation: m∠DAY+m∠MON+180
m∠DAY=m∠MON-20
m∠MON+4m∠MON-20=180
Work:
m∠O+4m∠O-20=180
-20 -20
m∠O+4m∠O=160
+4 +4
m∠O+m∠O=164
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Instead of DAY and MON, I'll use X and Y.
X%2BY=180
X=4Y-20
Substituting,
%284Y-20%29%2BY=180
Add 20 to both sides
5Y-20%2B20=200
5Y=200
Divide both sides by 5,
Y=40
Then,
X%2B40=180
X=140
So m