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5. Determine a scalar equation for the plane through the points M(1, 2, 3) and N(3 ,2, -1) that is perpendicular to the plane with equation 3x + 2y + 6z + 1 = O. 6. Show that the line with parametric equations x = 6 + 8t, y = -5 + t, z = 2+ 3t does not intersect the plane with equation 2x - y - 5z - 2 = 0 7. Explain why there are many different vector and parametric equations for a line