The steps shown can be used to prove that the medians of a triangle meet at a point. Triangle A B C is shown on an x and y-axis. Lines are drawn from each point to the opposite side and intersect at point G. Point A is at (0, 0), point D is at (c, 0), point C is at (2 c, 0), point B is at (2 a, 2 b), and point E is at (a, b).

1. Define segments BD and CE as medians of triangle ABC.
2. Write linear equations for Line B D and Line C E.
3. Use a system of linear equations to solve for the coordinates of intersection point G.
4. Write the equation of Line A G.
5. Write an expression for the midpoint of BC, point F.
6. ?
Which is the final step to complete the proof?

Write a linear equation for each side of the triangle.
Write an expression for the midpoint of AC and BC.
Show that A F is congruent to BD and CE.
Show that A F is the median of BC.

An annual marathon covers a route that has a distance of approximately 26 miles. winning times for this marathon are all over 2 hours. the following data are the minutes over 2 hours for the winning male runners over two periods of 20 years each. earlier period 14 12 15 22 13 10 19 13 9 14 20 18 16 20 23 12 18 17 6 13 recent period 7 11 7 14 8 9 11 14 8 7 9 8 7 9 9 9 9 8 10 8 (a) make a stem-and-leaf display for the minutes over 2 hours of the winning times for the earlier period. use two lines per stem. (use the tens digit as the stem and the ones digit as the leaf. enter none in any unused answer blanks. for more details, view how to split a stem.) minutes beyond 2 hours earlier period 0 1 2 (b) make a stem-and-leaf display for the minutes over 2 hours of the winning times for the recent period. use two lines per stem. (use the tens digit as the stem and the ones digit as the leaf. enter none in any unused answer blanks.) minutes beyond 2 hours recent period (c) compare the two distributions. how many times under 15 minutes are in each distribution