Answer:
The answer is 15 units.
Step-by-step explanation:
If you count the number of units from point A up to the same Y coordinate as point B, the amount of units is 9.
Then, the number of units from that point over to point B is 12 units.
Using this information, you can use the Pythagorean theorem to find that 9 squared is 81, 12 squared is 144, add 144 and 81 to get 225, and then you can find the square root of 225 which equals the answer of 15 units.