Question 843654
You know that y=6+(5x) and that x+y=180.
Plug the first equation into the second for y.
x+6+5x=180.
Next combine like terms: 6x+6=180
Subtract 6 from both sides: 6x=174
Divide by 6 on both sides: x=29°
Plug x into the original equation: 29+y=180
Subtract 29 from both sides: y=151°