15. Determine the distance that the dog moved

A boy observes a dog, at an angle of 30$^{\circ}$ from the top of the building, 15 $m$ above the ground. The dog runs towards the building from a distance, and its angle from the top of the building is $45^{\circ}$. Find the distance the dog has moved. (Use $tan \ 30^{\circ} = 0.577$)

 

Answer:

 

The dog moved about a distance of  $m$.