The equation of a line in slope-intercept form looks like this:
y=mx+b
Where m is the slope and b is the intercept of the line with the y-axis.
We can rewrite our equation to make them look like the expression above like this:
Equation A
4x - 2y = -6
4x - 4x - 2y = -6 - 4x
-2y = -6 - 4x
-2y/-2 = (-6-4x)/-2
y = 3 + 2x, this is how equation A look like in slope-intercept form.
Equation B
3x + y = 3
3x - 3x +y = 3 - 3x
y = 3 - 3x, this is how equation B look like in slope-intercept form.
To graph these lines, we just have to find two points of them ( a pair of points for each line), then join them, we can find points of the line by replacing values of x and calculating its corresponding value of y.
Let's take for example x=0
Equation A
y = 3+2*0=3, then we have the point (0,3)
Equation B
y=3-3*0=-3, then we have the point (0,3) (like in equation A)
Now let's take x=1
Equation A
y=3+1*3=3+3=6, then here we have another point (2,6)
Equation B
y=3-3*1=3-3= 0, (2,0)
Now that we now two points of the line described by equation A (0,3) and (2,6) and two points for the equation B (0,3) and (2,0), let's plot them, like this: