Question

why they have used only third equation of motion in this question why not they have used any other equation of motion .

please explain me.
contains 20 points​

Answer 1

because initial and final velocity. and displacement is given

and t is not given

Answer 2

Answer:

Explanation:   They have used only the third equation because , in the question the (time) is not mentioned .    

If the time is given we can use 2nd and  3rd equation....