Given the linear equation

We can find the y-intercept by setting x=0 and solving for y, as shown below

To graph a linear equation, we need two points on it. We already have one (0,3), we can find a second one by setting x=1 and solving for y

Draw both points on the plane and cross them with a line, as shown in the image below
Where A=(0,3) and B=(1,7)