1. 2.1Real Numbers
Objective: Students will be able to identify real numbers on a number line and be able to describe what an absolute value is. They will also be able to create counter examples to problems.

2. Notes Real numbers: rational and irrational numbers.
Real Number Line: showing numbers on a horizontal line.
Origin: point located at 0.
Negative numbers: points left of zero.
Positive numbers: numbers right of zero.
Integers: negative/positive numbers and zero.

3. Notes Graph: point that corresponds with a number.
Plotting: drawing a point.
Graph the numbers on a number line.
0, -2, 4.5, 3 ¾, -5

4. Number Line – Graph the numbers on a number line.
-1/2, -3/4, -2, -5/4
3, -6, -3, 1, 5, -4, 2.5

5. Compare numbers 4 ____ -2 -6 ____ -5 -5 ____ -6 2.4 ____ -2.5
4 ____ ____ ____ ____ -2.5
5.1 ____ ____ ____ -44 ½ ___ ¾

6. Notes Opposites: two points same distance from zero but opposite side.
Ex: 3 opposite -3
Absolute value: distance between o and any point.
Sign: x
Find the opposites. -4 5
Find the absolute value of 6 and -7.

7. Opposites/absolute value
Find the numbers opposite
Find the absolute value
4/5 2 -1 -8

8. Notes Velocity: indicates speed and direction.
Speed: absolute value of velocity.
Counter example: using an example to prove something is false.
A space shuttle launch pad elevator drops at a rate of 10 ft. per second. What’s the velocity and speed?
Find a counter example
Opposite of a number is always negative.
The expression –a is never positive.

9. Velocity and counterexample
I climbed a stair case at 5 steps per second. What’s the velocity and speed?
Find a counter example. The absolute value of a number is never negative. The expression –a is sometimes greater than a.

10. Wrap up
Questions/Comments
Hw: text pg. 67, #’s: 2-60 even