Two drones hover at A(6, -2, 10) and B(-4, 8, 2), with distances in metres measured from a pole at…

The point that divides $AB$ internally in the ratio $m : n$ is $\dfrac{mB + nA}{m + n}$, coordinate by coordinate. For an external division use $\dfrac{mB - nA}{m - n}$. A coordinate plane such as $x = 0$ divides $AB$ in the ratio $-x_1 : x_2$.