The image of the point (1,2,−1), on the plane containing the line x+1−3=y−32=z+21 and  the point (0,7,−7) , is

Given x+1−3=y−32=z+21……..(1) and point (0,7,−7) The equation of the plane is x+1y−3z+214−5−321=0⇒(x+1)(4+10)−(y−3)(1−15)+(z+2)(2+12)=0⇒14(x+1)+14(y−3)+14(z+2)=0⇒x+y+z=0………...(2) The image of the point (1,2,−1) on the plane (2) is h−x1a=k−y1b=l−z1c=−2(ax1+by1+cz1+d)a2+b2+c2⇒h−1=−43⇒h=−13 And ⇒k−2=−43⇒k=23 And l+1=−43⇒l=−73∴ Image of (1,2,−1) is −13,23,−73