Respuesta :

so midpoint of ab is (2,5) and b is (5,7). so since ab is the midpoint that means that point a and b are equaditant to the midpoint.
2+x=5
x=3 
so i subtract 3 from 2 which is -1
5+x=7
x=2
so i subtract 2 from 5 and get 3
therefore point A is (-1, 3)