y = 5x – 9, y = 2x + 6 ;
Substitution method:
5x – 9 = 2x + 6 ;
5x - 2x = 6 + 9 ;
3x = 15 ;
x = 15/3 ;
x = 5 ;

y = 5(5) – 9 ;
y = 25 - 9 ;
y = 16 ;

Solution set: (5, 16)