The middle point of the line segment joining (3, −1) and (1, 1) is shifted by two units (in the sense of increasing y) perpendicular to the line segment. Find the co-ordinates of the point in the new position.
Let P be the middle point of the line segment joining
Then
Let P be shifted to Q where PQ = 2 and y co-ordinate of Q is greater than P 
Now slope of AB = –1
slope of PQ = 1
Co-ordinates of Q by distance formula
as y co-ordinates of Q is greater than that of P.
Hence, is the required point.
Study 40% syllabus and score up to 100% marks in JEE