I come to know that IMAGE OF A LINE IN A PLANE has big process to have answer. Sir please provide me the solution and short tricks (if any)

Let the plane be accepted+by+cz+d=0..We need to find image of a point(x1,y1,z1) in the plane.. let the image be (h,k,l).The formula is .(h-x1)/a = (k-y1)/b= (l-z1)/c= -2(ax1+by1+cz1+d)/(a²+b²+c²).To find h,k,l equate each term to last one and hence find image..