Hi

I'm new to the forum so I hope I'm posting in the correct place.

Anyway, there's a question that I'm really stuck on, I know it's probably simple but I can't seem to see where I'm going wrong. If anyone could help with how to work it out, I would be so grateful. Here it is:

In the following diagram, AB=8.5m is the perpendicular height of a pole, and CD=6.9m is the perpendicular height of a second pole. The angle CDB is 100º. Calculate:

a) the distance AC between the base of the poles. (2d.p.)

b) the length of BD, the distance between the tops of the poles. (2d.p.)

Thanks in advance.