The equation for this is (y-y)=m(x-x)
The second y and the second x are a set of coordinates the line passes through. The mis the slope.
Answer:
y+2=-3(x-1)
Take the coordinates:
The y coordinate = -2
The x coordinate = 1
If you take the coordinates from this equation (1,-2), you see that this line does in fact pass through it.
That -3 is the slope and to make sure that -3 is right, go to the graph. When you look at it you see going going from point (0,1) to point (1,-2) the slope is in fact -3 (because you go down three and over one).