What are the coordinates of point A math help

the coordinates of the midpoint of AB is (2,4)
the coordinates of point B are (3,7)
what are the coordinates of point A
i really don't get this and i need help

Perhaps it is easiest to set it up as an equation.
let A = (x1, y1) and B = (x2, y2) = (3,7)
(x2-x1)/2 = (3-x1)/2 = 2
(3-x1) = 4
x1 = -1

(y2-y1)/2 = (7-y1)/2 = 4
7-y1 = 8
y1 = -1

so the coordinates of A are (-1, -1)

Hope that helps.