geometry
posted by zach .
Given three collinear points X, Y, and Z and XY=8 and YZ=20, what is the length of a segment joining the midpoint XY and YZ?

Draw line segment XZ and let X = 0, the
starting point.
Xy = Y  0 = 8,
Y = 8.
M1 = (80) / 2 = 4 = Midpoint of XY.
YZ = Z  Y = 20,
Z  8 = 20,
Z = 28.
M2  Y = 20 / 2 = 10,
M2  8 = 10,
M2 = 18.
Segment M1M2 = M2  M1 = 18  4 = 14.