Algebra Adventures for Year 5

Discovering the Magic of Unknown Numbers An Introduction to Basic Algebra

What is Algebra?

Algebra uses letters to represent unknown numbers We call these letters 'variables' Variables help us solve problems when we don't know all the numbers Common variables are x, y, and n

Mystery Number Game

Think of a number Add 5 to your number Your answer is 12 What was your mystery number?

Writing Algebraic Expressions

An expression uses numbers, variables, and operation symbols Example: x + 3 means 'a number plus 3' Example: 2y means 'two times a number' Example: n - 4 means 'a number minus 4'

Words to Algebra Translation

{"left":"A number plus 7\nx + 7\nThree times a number\n3n","right":"A number minus 2\ny - 2\nHalf of a number\nn ÷ 2"}

Quick Check!

How would you write 'a number plus 8' in algebra? What about 'five times a number'? Turn and tell your partner!

Simple Equations

An equation has an equals sign (=) Both sides must be equal Example: x + 4 = 9 We need to find what x equals

Solving Equations Together

Let's solve: x + 6 = 11 What number plus 6 equals 11? Try different numbers! Check your answer by substituting back

Algebra Detective Steps

Algebra Adventures Summary

Variables are letters that represent unknown numbers Expressions combine numbers, variables, and operations Equations show that two expressions are equal We solve equations to find the value of variables Always check your answers!