Medians and Altitudes

1
Medians and Altitudes

• Medians

2
Review Angle Measures

• DB is the bisector of angle ADC. What is the
  measure of angle ADC?

3
Review Concurrency of Angle Bisectors

• What is the length of segment BG?

4
Review Midsegments

• MN is the midsegment of triangle ABC. What is the
  length of MN and AB?

5
Median of a Triangle

• The median of a triangle is a segment from a
  vertext to the midpoint of the opposite side.

6
Guided Practice

• Segment CM is the median of triange ABC. What is
  the length of segment AM?

7
Centroid of a Triangle

• The centroid of a triangle is the point where the
  three medians meet. The centroid is 2/3 of the
  distance from the vertex to the midpoint of the
  opposite side.

8
Centroid of a Triangle

• G is the centroid of triange ACE, FE 4, AG 6,
  and CF 12. What is the length of FG, GC, GD,
  and AF?

9
Altitude

• An altitude of a triangle is the perpendicular
  segment from a vertex to the opposite side or to
  the line that contains the opposite side.

10
Median? Altitude? Perpendicular Bisector? A
recap

• What is the difference between a median,
  altitude, and perpendicular bisector?
• A median goes from a vertex to the midpoint of
  the opposite side. It bisects the segment.
• An altitude goes from a vertex to intersect the
  opposite side at a 90o angle.
• A perpendicular bisector is both a median and an
  altitude. It goes from the vertex to the opposite
  side, bisecting that segment at a 90o angle.

11
Homework

• Workbook, pg 61 62
• Problems 1 22
• Workbook, pages 91 93
• 1 3, 7 16, 18
• Workbook, pages 94 - 95
• 1 6, 10 24