Given: the coordinates of triangle pqr are (0,0), q(2a,0), and r(2b,2c). prove: the line containing the midpoints of two sides of a triangle is parallel to the third scale.
as part of the proof find the midpoint of qr

a) (a-b, c)
b) (a+b, c)
c) (a, c)
d) (b, c)