Find the average acceleration of a northbound subway train that takes 0.90 seconds to go from 12 m/s to 4.5 m/s.

a= -8.33

Step-by-step explanation:

it will be deceleration because he was 12 m/s then go to 4.5 m/s

and by applying moving equation

=+at

we have all but not have a  

a and c

for infinitely many solutions we require both left and right sides to be equal

distribute and simplify

a

14 - 8x = 20 - 8x - 6 = 14 - 8x ← both sides equal so infinite solutions

b

6x - 54 = 6x - 54 + x = 7x - 54 ← not equal

c

4x + 16 = 4x + 10 + 6 = 4x + 16 ← both sides equal so infinite solutions

d

5x - 40 + 10 = 5x + 10

5x - 30 = 5x + 10 ← not equal