Find the coordinates of the foot Q of the perpendicular drawn from the point P(1,3,4) to the plane Find the distance PQ and yhe image of P treating the plane as a mirror.
Consider the figure.
Equation of PQ :
coordinates of the random point on the lines is . As Q lies on the plane
The foot of perpendicular is
let be the image of P in the plane.
clearly Q is the midpoint of PM so
On comparing, the coordinates we get