Okay, here we have this:
Considering the provided equation, we are going to graph it using the slope and y - intercept, so we obtain the following:
We can see that the equation has the form: y=mx+b, where the m represents the slope and the y represents the y-intercept. Then in this case:
In y = - 1/3x - 4, the slope is -1/3 and the y-intercept is -4.
Now, from the y-intercept we know a point of the equation (0, -4) and the other point we calculate using the slope, we know that the slope tells us that from a known point we can obtain another to rise the quantity of the numerator and run the quantity of denominator units, then in this case from the y-intercept point we go down one unit and move three to the right, we get the following point (0+3, -4-1)=(3, -5).
Finally graph these points and join them by a straight line, that straight line will be the graph of our equation: