The x value is given x=-2, the point ( -2,y) is ( x,y) is a point on the line 3x-6y = 12, so you need the value of y.
Substitute x = -2 into the equation, (3)(-2)-6y=12, -6 -6y =12, and
Add +6 to both sides, +6-6-6y=12+6, -6y = 18, divide by -6,
(-6y/-6) = (18/-6), y = -3 then the solution to this equation is ( -2,-3)
Check by substituting x=-2 and y=-3 into equation
3(-2) -6(-3) = -6+18 = 12 and therefore checks
The point ( -2,-3) is on the line 3x-6y =12 and it is one of the solutions, please remember that there are many other solutions to this equation of line with different values of x and corresponding value of y or vice versa.
