The y-intercept is the point where the line crosses the y-axis,
this line crosses the y-axis in -4
then, b = -4
Slope
I found 2 points of the line
P1 = (0, -4) and P2 = (5, 2)
slope = (y2 - y1) / (x2 - x1)
slope = (2 - (-4)) / (5 - 0)
slope = (2 + 4) / 5
slope = 6/5
m = 6/5