Unit 4- Adding and Subtracting

Summary of Knowledge

Do you remember the black and red chip boards? In this investigation we used those chip boards, and numberlines to learn how to make addition and subtraction opperations with positive and negative numbers. We understood different patterns to solve there operations.Many of us noticed that if you add a positve and a positive the answer will be positive ans if you subtracta a negative and a negative the answer will be greater than the initial number. Not only this but much more.

Key Vocabulary

Commutiative: The order of additon may change and the answer will be the same.

Absolute value: The distance from zero on a numberline.

Algorithim: A set of rules to preform an opperation.

Integer: A whole number that has opposite
Example:1/-1

Sum: The result of an addition.

Product: The result of a subtraction.

Positive number: A number greater than zero(0).

Negative number: A number smaller than zero(0).

Opposites: A positive and a negative number that haved the same distance from zero(0).

Task Analysis

Positive and negative (whole) numbers

1.Write your opperation.

2. Locate the first number on a numberline( on a paper or your head).

3. Change the opperation to a single sign( task analisys #2).

4.Answer.

5. Check by repeating process.

How to Change the Sign
1. When you have:
(+n)+(-n) =(+n)-(+n)

(+n)-(-n)= (+n)+(+n)
(+n)+(+n)= (+n)+(+n)
(+n)-(+n)= (+n)-(+n)
Addition is commutative so if negative sign is first you can put it second then change the sign.

2. Opposites

*(-s)+(+s)=0

* When both numbers,(not the sign) are the same digit, the answer will always be zero.

Example:(-4)+(+4)=0

Fractions adding and subtracting