Problem $24\mathrm{.}10$

A long wire carrying a $6\mathrm{.}0$ A current perpendicular to the $xy-$plane intersects the $x-$axis at $x=-2\mathrm{.}0cm.$ A second, parallel wire carrying a $2\mathrm{.}0$ A current intersects the $x-$axis at $x=+2\mathrm{.}0cm.$ At what point on the $x-$axis is the magnetic field zero if the two currents are in the same direction? At what point on the $x-$axis is the magnetic field zero if the two currents are in opposite directions?