The first is knowing what the numbers in your equation represent:
For example: y=mx+b in this case "b" is 9. b is the y-value when x=0. So the first point on our graph is (0,9). Next we have to pick an xvalue to solve for another y-coordinate.
I chose x= -3. Plug x into the equation to get y. y=3x+9 y=3(-3)+9 y=(-9)+9 y=0
So, our second point is (-3,0).
connect the points with a ruler to graph the line.
