The equation of the line in Slope-Intercept form is:

Where "m" is the slope and "b" is the y-intercept.
So, we must write each equation in Slope-Intercept form. We can do that solving for "y".
For Equation 1:

We can see that:

Knowing those values, we can graph the line.
For Equation 2:

For this line:

Knowing those values, we can graph the second line.
See the graph attached.
Observe that they intersect each other at the point (4,-6). That point of intersection is the solution of the System of equations:
