1

1

1

1

1

O - B

Time t

AB^2=A0^2+BO^2

Derivation of t

2AB dAB/dt=2AO dAO/dt+2BO dBO/dt

At 12: 30, ao =18-0.5 * 24 = 6bo =16 * 0.5 = 8ab =10.

dAO/dt=-24 dBO/dt= 16

You can get DAB/DT =- 1.6 by substitution.