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Question
Point A ( 4,-1) is reflected as A' in the line x= 1. Point B on reflection in the line y=3 is mapped as B' (6,-1). Write the co-ordinates of A' and B. Write the co-ordinates of mid.-ooint of the line sgment A' B'.
Solution
A (4,-1), the co-ordinates of A'= (2x1-4,-1) = (-2,-1)
A' (6,-1), the co-ordinatesofB = (6, 2x3-(-1)) = (6, 7)
The distance between A' B'
= `sqrt ((6 - (-2))^2 + (-1 -(-1))^2)`
= `sqrt (8^2 + 0)`
= 8 units
Distance till midpoin t = 4 units
Co-ordinates of mid-point = ( -2 +4, -1 +4) = (2, 3)
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