# Basic Algebra/Introduction to Basic Algebra Ideas/Chapter Review

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## Contents

## Lesson 1. Simple Operations[edit]

An *operation" is a thing you do to numbers. You use signs like: +, –, × , or ÷ for operations.* The Equals Sign is not an operation.

- Adding
- Adding is a way to put two numbers together.

- 1 + 2 = 3

- Subtracting
- Subtracting is a way of taking a number out from another number.

- 2 – 1 = 1

- Multiply
- Multiplying is a way of adding a number many times

- 3 × 2 = 6

- Dividing
- Dividing is a way of subtracting a number many times.

- 6 ÷ 2 = 3

- Example Problems

- 2 + 1 = (3)
- 8 + 2 = (10)
- 8 – 4 = (4)
- 5 – 2 = (3)
- 6 × 2 = (12)
- 2 × 3 = (6)
- 12 ÷ 6 = (2)
- 4 ÷ 2 = (2)

## Lesson 2. Exponents and Powers[edit]

Exponent is the number on the top that shows.

Base is the number to be multiplied by itself.

**Example Problems**

- 6
^{2}(36) - 2
^{3}(8) - 4
^{2}(16) - 5
^{3}(125) - 2
^{4}(16)

## Lesson 3. Order of Operations[edit]

Math problems are done in this order from top to bottom:

- Parenthesis ( )
- Exponent ^
- Multiply *, Divide / (Left to Right)
- Add +, Subtract – (Left to Right)

**Example Problem**

2^{2} + (3 * 4) |
Original problem. |

2^{2} + (12) |
Do parenthesis first. |

2^{2} + 12 |
Do exponent. |

4 + 12 | Add. |

16 | Answer |

## Lesson 4. Working With Negative Numbers[edit]

A positive number is a number more than zero.

A negative number is a number less than zero.

**Example Problems**

- 6 + (–3) = (3)
- 3 + (–9) = (–6)
- –4 * 4 = (16)
- 4 * (–9) = (77)
- –2 * (–4) = 8

## Lesson 5. Solving Equations Using Properties of Mathematics[edit]

It is very important to show math in the simplest way. For example, 5/10 is the same as 1/2, but 1/2 is better because it is easier to understand. The simplest answer is usually the best.

**Example Problems** -- find x when y=9

- x = 8( y / 3 )(x=24)
- ( x – 4 ) = 8 + y (x=21)
- ( 14 + x ) / y = 3 (x=13)