the distance between the two knights are d = s1 +s2 = 88 m
accelaration of the knight is a1 = 3m/s^2
accelaration of the second knight is a2 = 2 m/s^2.
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Let they collide after time ' t ' at point C then
the accelaration of the first body is a1 = s1 / t^2
t^2 = s1 / a1 ---------------(1)
the accelaration of the second body is a2 = s2 / t^2
t^2 = s2 / a2 ----------------(2)
from (1) & (2) we get s1 / a1 = s2 / a2
and s1 +s2 = 88 m
solving these equations we get s2 = 35.2 m
35.2 m away are they from the second knight when they collide
solving these equations we get s1 = 52.8 m
52.8 m away are they from the first knight when they collide