It would be best to draw the problem described above. Sketching it, you will see that a right triangle would be formed from the description where the vertical distance of the dog to its owner is the height of the triangle and the angle of elevation of the triangle would be 10 degrees. The hypotenuse of the triangle represents the distance of the dog from its owner. By using trigonometric functions, we can easily calculate for this value. We use the sine function which is equal to the opposite side divided by the hypotenuse.
sine 10 = 30 feet / hypotenuse
hypotenuse = 172.76 feet ( distance of the dog to its owner )