Answer:
Let's start by finding the speed of the dog:
Dog's speed = 2 * Cat's speed
Dog's speed = 2x mph
To find how far away they will be after 30 minutes, we need to first find the distance each one travels in that time.
Distance = Speed * Time
Cat's distance = x * 0.5 = 0.5x miles
(30 minutes = 0.5 hours)
Dog's distance = 2x * 0.5 = x miles
Now we can find the total distance between them:
Total distance = Cat's distance + Dog's distance
Total distance = 0.5x + x
Total distance = 1.5x miles
So after 30 minutes, the cat and dog will be 1.5x miles away from each other.