1. Find the position of possible multiple points on the curve r (z - y) + y = 0. 2. For what value of A, the equation, Aa10xy + 12y2+5-16y-3 = 0 represents pair of straight lines. 3. Find the point of intersection (if it exists) of the pair of lines L: 2-2 = 4+1 and M: *+1 y-3 2-5 = = 7 3 = 3 4. Find equation of the straight line through the point (2,4,-3) and perpendicular to the plane 3x+3y 7z - 9 = 0. 5. Show that equation of the tangent to the ellipse + 1 at point (21) is a = 6. Find the surface of revolution obtained by revolving the curve + y about z-axis. == 5:, J = 1) 7. Convert the equation, p = 7 sin sin o. from spherical co-ordinates (p, 0, 0) into cartesian co-ordinates. 8. Find the traces of the surface + - 3 = 1 in xy- plane and yz- piane. 9. Find equation of the sphere with center at (-2,4,-6) and tangent to zz-plane. 10. Find centre and radius of the sphere x + y + z+2x-4y6z + 5 = 0.