Answer: 3x + y = 0
Step-by-step explanation: Remember that slope is represented by
rise over run from one point to the next on our graph.
To get from the point (0, 0) to (3, -9), we go down -9 units
so our rise is -9 and we run 3 units so our run is 3.
Our slope therefore or m = -9/3 or -3.
Our y-intercept is represented by the point where this line
crosses the y-axis which in this case is up 0 units.
So our y-intercept or b = 0.
Since we have the slope and y-intercept of our line,
we can now write its equation in y = mx + b form.
Since m = -3 and b = 0, that gives us y =-3x + 0.
Now we convert this equation to standard form.
Just add 3x to both sides to get 3x + y = 0.
So the equation of this lie is 3x + y = 0.
