The midpoint qr is m (-1,2). one endpoint is r (3,4). find the coordinates of the other endpoint.

M = (x₁ + x₂)/2  , (y₁ + y₂)/2

(-1, 2) =

At this point, it is easier to separate the x's and y's into two different equations:

x's: -1 =

     -2 = 3 + x

     -5 = x

y's: 2 =

     4 = 4 + x

     0 = x

(-5, 0)

so, converting firstly the mixed fractions to improper fractions and then "adding".