AP EAMCET Engineering 2018 Apr 24 Shift 1 Paper

Mid-point of the line joining the points (2,0,6) and (-6,2,4)is (-2,1,5).
Direction ratio of the line segment joining the points (2,0,6)and (-6,2,4)
=(−6−2),(2−0),(4−6)
=−8,2,−2=a1,b1,c1
Direction ratio of line joining (x,y,z) and (-2,1,5) are
=(x+2),(y−1),(z−5)
The relation between direction ratio is
a1a2+b1b2 +c1c2=0
−8(x+2)+2(y−1)−2(z−5)=0
−8x+2y−2z−8=0
4x−y+z+4=0