Question 614429
  <pre><font face = "Tohoma" size = 3 color = "indigo"><b> 
Hi
 {{{Pt(3.5,2)}}} is the Midpoint of Q(1,8)and R(x,y)
Midpoint Pt(x,y):  ( {{{(x[1] + x[2])/2}}}, {{{(y[1] + y[2])/2  )}}})
Q(1,8)
R(x,y)  (1+x)/2={{{3.5}}}, x = 6  and  (8+y)/2 = {{{2}}}, y = -4
R(6,-4)is the pt at the other end of the diameter QR