Question

How do you graph `-x + 3y = -9` by plotting intercepts?

Answer 1

The intercepts are found where `y=0` and `x=0`

Explanation:

To find the y-intercept we make `x=0`. Thus `3y=-9`, and so `y=-3`. This means that the straight line passes through the point `(0, -3)`. Similarly, when `y=0` we have `-x=-9`, that is `x=9`, so the line passes through `(9, 0)`. Now, you need to plot the two points, and draw the line through them.

graph{1/3x-3 [-10, 10, -5, 5]}