Question

An isosceles triangle ΔABC has its altitude at the y-axis and its base at the x-axis. D is the midpoint of segment AC and E is the midpoint of segment CB. Given the coordinates A(-2a, 0), B(2a, 0), and C(0, 2b), determine the coordinates of midpoints D and E.
a.)D(2a,-b); E(-a,b)
b.)D(-a,b); E(a,b)
c.)D(0,2b); E(2a,0)