Calculus

7. Find the equation of the line that is perpendicular to r2 =< -2t, 5 + t, -4t> and the z-axis that also goes through the intersection of r2 and the z-axis.

16. A 500 kg load is held from three cables. The cables are of equal length. The cables are anchored at the shown points. Find the vectors that represent the forces on the cables due to the load.