1. April 17, 2012 Midpoint and Distance Formulas
Warm-up:
Think back to Geometry…
How would you find the
length of the side AC?

2. Distance Formula Activity
Graph the segment
between A(-3, 6) and B(4, -4).
2. Using only horizontal and
vertical segments, make a right
triangle with the segment AB.
3. Find the length of each side.
4. Use the Pythagorean Thm to
find length of AB.

3. Example 1: Using the Distance Formula
Find the distance between the points
(2, -4), (10, -10)
(x1, y1) (x2, y2)

4. Example 2: Midpoint Formula
Finding the midpoint is like finding the average of the value of x and y. Find the midpoint of the line segment with the endpoints (-5, 3) and (-3, -7).
(x1, y1) (x2, y2)

5. Find the midpoint of the line segment (8, 3) and (16, 7)
Find the midpoint of the line segment (8, 3) and (16, 7). Then use the distance formula to prove that it is midpoint.
Find the distance between (8, 3) and (16, 7).
Then find the distance between one of the points (8, 3) and the midpoint (12, 5).
Yes, (12, 5) is the midpoint between (8, 3) and (16, 7)

6. Go to www.algebra2.com/self_check_quiz
Chapter 8 – Conic Sections
Lesson 1 – Midpoint and Distance Formulas