Day 1 agenda

1
Day 1 agenda

• Return/go over chapter 4 test- 15 min
• Notes- 40 min
• Practice- 25 min
• Group assignment with graph paper
• Start homework- 10 min

2
Perimeters, Midpoints, and Parallel lines

• Todays goalsBy the end of class today, YOU
  should be able to

1. Find the perimeter and midpoints of any
triangle. 2. Identify parallel lines.
3
The Distance Formula
The distance, d, between any points with
coordinates (x1, y1) and (x2, y2) can be found by
using the distance formula.
d v(x2-x1)2(y2-y1)2
4
Ex.1 Finding the distance between two points of
a triangle

• Find the distance between the pair of points with
  the given coordinates (4,12) (4,10)

5
Ex.1 Solution
6
You try

• Find the distance between the pair of points with
  the given coordinates
• (7,7) (-5,-2)
• (-1,4) (1,4)

7
Review

• What is perimeter?

The total distance around an object.
8
You try finding the perimeter of atriangle
HINT Use the distance formula

• Find the perimeter of a triangle with the given
  coordinates (3,-5) (3,4) (0, 2)

9
The Midpoint Formula
The middle point of a line segment is called the
midpoint. It is equidistant from both endpoints.
M ((x1x2)/2 , (y1y2)/2)
10
Ex.2 Finding the midpoint of a line segment
Find the midpoint of a line segment with the
given coordinates (7,8) (5,10)
11
Ex.2 Solution
12
You try
Find the midpoints of the line segments with the
given coordinates 1. (3,4) (5,4) 2.
(3,9) (-2,-3)
13
Review

• Parallel lines are two lines in a plane that
  never intersect or meet.
• The parallel symbol is ll. For example, AB ll CD
  indicates that line AB is parallel to line CD.

14
Practice

• Pair students up with their neighbors
• Give each pair 3 sheets of graph paper, and ask
  them to plot a triangle on each one (label all
  axes and points)
• Student may use rulers to draw their triangles,
  but not to find the perimeters or midpoints
• Have them switch graphs with another group, and
  find the perimeter and midpoints of each of the
  three triangles

15
Homework

• Pass out the following worksheet for students to
  begin when they finish with the practice
  assignment. Have them finish it for homework
• http//teachers.olatheschools.com/fishelprealgebra
  /files/2009/03/113-practice.pdf
• Have the students write a short reflection in
  their math journals on what topics they struggled
  with on the chapter 4 test and why.