Answer: 346.4
Step-by-step explanation:
The whole triangle ABD is a 30-60-90 right triangle. In 30-60-90 triangles, the smallest side is x, the middle side is x, and the largest side/hypotenuse is 2x.
Side AB is the smallest side and therefore x=300. Side BD is the middle side and so we can use x and we get BD=300
=519.615
The question is asking for CD, and we know that CD can be equal to BD minus BC since that would isolate CD
Triangle ABC is also a 30-60-90 triangle but the 300 feet is the middle side in this triangle. So we can do 300=x and divide 300 by radical 3 and get that x=173.205
Side BC is the smallest side of this triangle so it would be x and x is 173.205.
Now that we have the whole side BD and the part of it BC. We can subtract BD by BC (519.615-173.205) and we get that CD=346.4