What if most common factor of 42 and 15

(1, 3)

Step-by-step explanation:

There are two ways to solve this problem, 1 without the pythagorean theorem, and 1 with it.  For the sake of simplicity, I will solve it without the pythagorean theorem.

As is visually evident from the graph, the line segment spans 6 units horizontally, and 3 units vertically.  Because the ratio between AP and PB is 1:2, simply divide both the domain and range by 3, to get 2 horizontally, and 1 vertically.  

Then, simply go to point A and respectively add and subtract the horizontal and vertical values to get point A(-1, 4) --> P(1,3)

Hope it helps, and let me know if you want me to solve it an alternate way or go more in depth as to the way it is know.