To solve this, use one method which is elimination. To eliminate, add or subtract(I prefer add) the 2 equations
Divide both sides by 5
After you find the value of a number, substitute.
Now, to graph this, we can use methods like intercept form
Coordinates of first equation:(0,-3)(1,0)
These are coordinates, just make a line crossing these points
The second equation
coordinates of 2nd equation: (0,2)(1,0)
Just connect a line between these 2 points.
Hope this helps =)