Answer:
So the correct answer is option B- ( b - a )
Step-by-step explanation:
Given that M and N are the mid-points of RT and ST.
We are to find the length of MN.
As shown in the figure,
the co-ordinates of the point T are (2c, 2d),
the co-ordinates of the point S are (2b, 0),
and
the co-ordinates of the point R are (2c, 2d).
Since M is the mid-point of TR, so the co-ordinates of M are
=(c+a,d).
Also, N is the mid-point of TS, the co-ordinates of N are
=c+b,d)(.
Therefore, the length of the line segment MN calculated using distance formula will be
MN==b-a.
Thus, the required length of MN is (b - a) units.
Option (B) is correct.