Uee two points on the line to find the slope.
(-1,2) and (1,-4)
Slope = change in y over change in x;
Slope = (-4 - 2)/ (1 - -1) = (-6/2) = -3/1 = -3
The y intercept is y value where the blue line crosses the y axis, which is at -1
The equation would be y = -3x-1
