We have the relation:
y = 4x + 3
Since the slope (4) and the y-intercept (3) were already found, we need now to graph this line.
In order to do so, we can find two points belonging to this line and then draw a line that passes through those points.
The first point can be (0, 3), since we know that the y-intercept is 3, i.e., y = 3 for x = 0.
Now, to find a second point we can choose a value for x, let's say x = 1, and use it in the equation of the line to find the corresponding value of y:
y = 4x + 3 , x = 1
y = 4 * 1 + 3
y = 4 + 3
y = 7
So, (1, 7) is another point we can use.
Now, we can select the second button on the toolbox to draw a line through the points (0, 3) and (1, 7):