Starter!

A brick and a half weighs a kilo and half a brick.

How much does a brick weigh?

Could we …

write this real life problem as an equation?

b + ½b = 1 + ½b

Learning Objectives:To solve equations with the unknown

on both sides of an equation

Learning Outcome:You can use the ‘balancing method’ to solve equations

What you will need to represent the equations:

Paper (or real) scalesx’s1’s

Solving Equations

Use your ‘scales’ to show this equation…2x + 4 = x + 6

Solving the equation … What’s the value of x ?

Remember to do the same to both sides of the equation …Remove ‘4’ from each side2x = x + 2Divide each side by ‘2’x = 2

Remember!

Always do the same to each side of the equation!

Keep your scales balanced!

E.g. 2x + 4 = x + 10 (- 4) 2x = x + 6 (- 4) (÷2) x = 6 (÷2)

Remember! In an equation, each letter stands for a missing number. To solve an equation, find the values of the missing numbers.

Remember! Adding and subtracting are the inverse (opposite) of each other.Multiplying and dividing are the inverse of each other.

1. Use your scales to represent an equation2. Solve the equation (to find the value of x)3. Write your method down

2x + 4 = x + 6

3x + 1 = 2x + 4

4x + 2 = 2x + 4

2x + 5 = x + 9

5x + 3 = 3x + 7

3x + 4 = 2x + 10

Remember!

Always do the same to each side of the equation!

Keep your scales balanced!

Online Interactive Activities

Balancing Method Activity: Available at http://www.mathsisfun.com/algebra/add-subtract-balance.html

Algebra Equations with a Balance Scale: Available at http://www.mathplayground.com/AlgebraEquations.html

Go to the website, click ‘create problem’ and type in the equation. Use the scales to represent the equation and solve!