math - given p3, p4 , m , how to find p1 and p2 -

math - given p3, p4 , m , how to find p1 and p2 -

given p3 p4 , m (midpoint of p1 , p2) , how find p1 , p2, please help.

p1(x1,y1) m(xmid,ymid) p2(x2,y2) --------------------------------- | | | | | | | | | | | | | | --------------------------------- p3(x3,y3) p4(x4,y4)

you can find midpoint of p3 , p4. difference m rectangle's missing side:

m34x = 0.5 * (x3 + x4) m34y = 0.5 * (y3 + y4) dx = xmid - m34x dy = ymid - m34y x1 = x3 + dx y1 = y3 + dy x2 = x4 + dx y2 = y4 + dy

math geometry coordinates