We know follwing formula
F=a*m
where F is RESULTANT force, a is acceleration and m is mass. We can transform that formula to obtain a, so
F=a*m /:m divide both sides by m
![\frac{F}{m}=a](/tpl/images/0750/8881/b9f1b.png)
Now we have to calculate resultant force acting.
We know that Dale and Alex push on opposite direction so we have to put minus in front on one of the forces and add it.
40+(-32)=40-32=8 [N] - resultant force acting on the couch
Now we have all necessary date, we can substitute.
a=
![\frac{F}{m}= \frac{8}{28} =0.29 \frac{m}{s^2}](/tpl/images/0750/8881/6196b.png)
- its the result