# Introduction to algebra

## Overview and history of algebra

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Origins of algebraAbstract-nessThe beauty of algebraIntro to the coordinate planeWhy all the letters in algebra?

## Introduction to variables

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What is a variable?Why aren't we using the multiplication sign?Evaluating an expression with one variableEvaluating expressions with one variable

## Substitution and evaluating expressions

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Evaluating expressions with two variablesEvaluating expressions with two variablesEvaluating expressions with two variables: fractions & decimalsEvaluating expressions with two variables: fractions & decimalsEvaluating expressions
Practice

## Evaluating expressions word problems

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Evaluating expressions with variables word problemsEvaluating expressions with variables: temperatureEvaluating expressions with variables: cubesEvaluating expressions with variables: exponentsEvaluating expressions review
Practice

## Writing algebraic expressions introduction

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Writing basic expressions with variablesWriting basic expressions with variablesWriting expressions with variablesWriting expressions with variables & parenthesesWriting expressions

## Introduction to equivalent algebraic expressions

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Equivalent expressions
Practice

## Dependent & independent variables

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Dependent & independent variablesDependent & independent variables: graphingDependent & independent variables: equation

## Combining like terms

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Intro to combining like termsSimplifying expressionsCombining like terms with distributionCombining like terms challenge problemSimplifying expressions with rational numbersCombining like terms review

## Interpreting linear expressions

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Interpreting linear expressions: diamondsInterpreting linear expressions: flowers

## Irrational numbers

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Intro to rational & irrational numbersClassifying numbers: rational & irrationalSquare roots and real numbers (old)

## Sums and products of rational and irrational numbers

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Proof: sum & product of two rationals is rationalProof: product of rational & irrational is irrationalProof: sum of rational & irrational is irrationalSums and products of irrational numbersWorked example: rational vs. irrational expressionsWorked example: rational vs. irrational expressions (unknowns)

## Proofs concerning irrational numbers

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Proof: √2 is irrationalProof: square roots of prime numbers are irrationalProof: there's an irrational number between any two rational numbers

## Division by zero

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Why dividing by zero is undefinedThe problem with dividing zero by zeroUndefined & indeterminate expressions

## Binary and hexadecimal number systems

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Introduction to number systems and binaryHexadecimal number systemConverting from decimal to binaryConverting larger number from decimal to binaryConverting from decimal to hexadecimal representationAdding in binaryMultiplying in binaryConverting directly from binary to hexadecimalHow to count to 1000 on two hands

#### Unit test

Test your understanding of Introduction to algebra with these 13 questions.