Answer:
-0.8 m/s²
Step-by-step explanation:
All you need to do here is find the slope of that line. And since it's a line, it doesn't matter what two points you pick to do it; since the slope is the same throughout.
Slope = (y_2 - y_1)/(x_2 - x_1)
But in this case:
- x = time (s)
- y = velocity (m/s)
*Which is where the units for acceleration come from.
I chose the points (0,12) and (4,10) to get:
Acceleration = Slope = (4-12)/(10-0) = -8/10 = -0.8 m/s²