Since it is a right triangle, we use trigonometric functions like tangent. With respect to the angle, tangent is the opposite side over the adjacent side. So,
tan 30 = x/300
x = 173.21 ft
Now, looking at the outer triangle, you want to find y which is the hypotenuse. The equation would be:
y = √[300² + (x+25)²]
y = √300² + (173.21 +25)²
y = 359.67
Thus, the distance is 360 feet.