Download LP.092314

_______North Seattle College____________________________________________________________
Math and Sciences Division
Mr. Thomas
Math 084: Lesson Plan
Date:
Tuesday, September 23, 2014
Homework: R.2 Page 13 Problems 15-39 (odd)
Due Wed, 9/24
Agenda:
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Attendance (2min)
Warm-up (3min)
Introduction to Integers (5min)
Adding and Subtracting of Integers (10min)
Multiplication and Division of Integers (10min)
Practice Problems (20min)
Warm-up: Can you get the number 24 from
4
4
4
3
? How about
4
3
3
?
3
(Using any combination of the basic four operations)
Introduction:
THE INTEGERS
The integers is a subset of the real numbers…they are also called signed numbers or simply negative and
positive numbers.
The set of integers is an infinite set {…-4, -3, -2, -1, 0, 1, 2, 3, 4…}
The set of integers is usually described on a number line:
The sum and difference of any two integers is still an integer. The product of any two integers is still an
integer. The quotient of any two may not be an integer. The set of integers is not closed under the
operation division.
_______North Seattle College____________________________________________________________
Math and Sciences Division
Adding and Subtracting Integers:
The easiest way to add and subtract integers is by using a number line, either one on paper or
mentally…
Example:
What is -2 + 5
Step 1
Step 2
Step 3
Example:
What is -5 - 2
Step 1
Step 2
Step 3
_______North Seattle College____________________________________________________________
Math and Sciences Division
Example:
What is 2 - 5
Step 1
Step 2
Step 3
*Note: Sometimes when you add or subtract integers, you have to do an extra step:
Example ( Can you tell the difference between these and the ones we just did? )
-2 – (-3) =
5 – (-1) =
-7 + (-1) =
3 + (-5) =
Multiplying and Division is quite different from Adding and Subtracting Integers
The following Rule is Instructive: (This rule holds for all Real Numbers, and therefore applies to the
Integers)
Positive */ Positive = Positive
Positive */ Negative = Negative
Negative */ Positive = Negative
Negative */ Negative = Postive
_______North Seattle College____________________________________________________________
Math and Sciences Division
Examples:
-3 * 4 =
(-2)(-6) =
4(-2) =
-16/2 =
12/-3 =
-6/-2 =
-----------------------------------------------------------------------------------------------------------------------------------------Practice Problems
Class work Page 13 Problems 2-24 (even)