Equation 1: 5x + y = 6
Equation 2: 3x - 3y = 18
Multiply all of equation 1 by 3.
1) 3(5x+y=6)
1) 15x + 3y = 18
2) 3x - 3y = 18
Add equations together.
18x = 36
Divide both sides by 18.
x = 2
Plug in 2 for x in first equation.
5x + y = 6
5(2) + y = 6
10 + y = 6
Subtract 10 from both sides.
y = 6 - 10
y = -4
So, your answer is a) -4
~Hope I helped!~
