Question 99527
3y+4=3x+y+3
3y+4+6x+20=180
.
rearange:
subtract 3x and y and 4 from each side: -3x+2y=-1
subtract 24 from each side: 6x+3y=156 
multiply 2 times the 1st equation:
-6x+4y=-2
6x+3y=156
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===7y=154
y=22 Ans.
replace y with 22 in the 2nd: 6x+66=156
6x=90
x=15 Ans.
angle 2 = 6x+20= 90+20= 110 Ans.
Check:
angle 1=3y+4=66+4=70
angle 3=3x+y+3=45+22+3=70
Ed