2.2.1
Rearranging Formulae
Rearranging Formulae
Rearranging Formulae
When rearranging a formula make sure that anything you do to one side of the equation you also do to the other side. To make x the subject of the
equation 3x - 9y = 4x - 24:


Subtract 4x from both sides
Subtract 4x from both sides
- We do this so that all the x terms are on one side.


Add 9y to both sides
Add 9y to both sides
- We do this so that all the y terms are on the other side.


Multiply both sides by (-1)
Multiply both sides by (-1)
- We have -x but we want x so we must multiply by -1.
Rearranging Formulae
Rearranging Formulae
If you square one side of the equation you have to square the other side of the equation too.


Square roots
Square roots
- To simplify a square root we can square both sides.


Square roots
Square roots
- If we square root an equation, we need to add a ± sign.
- Both +5 and -5 solve the equation x² = 25
1Numbers
1.1Integers
1.3Decimals
1.4Powers & Roots
1.5Set Language & Notation
1.6Percentages
1.7Ratio & Proportion
2Equations, Formulae & Identities
2.1Algebraic Manipulation
2.2Expressions & Formulae
2.3Linear Equations
2.4Quadratic Equations
2.5Proportion
3Sequences, Functions & Graphs
3.1Sequences
3.3Graphs
3.4Common Graphs
4Geometry
4.1Angles, Lines & Triangles
4.2Polygons
4.5Circle Properties
4.6Trigonometry & Pythagoras’ theorem
4.7Mensuration of 2D Shapes
4.83D Shapes & Volume
5Vectors & Transformation Geometry
6Statistics & Probability
6.1Statistical Measures
6.2Graphical Representation of Data
Jump to other topics
1Numbers
1.1Integers
1.3Decimals
1.4Powers & Roots
1.5Set Language & Notation
1.6Percentages
1.7Ratio & Proportion
2Equations, Formulae & Identities
2.1Algebraic Manipulation
2.2Expressions & Formulae
2.3Linear Equations
2.4Quadratic Equations
2.5Proportion
3Sequences, Functions & Graphs
3.1Sequences
3.3Graphs
3.4Common Graphs
4Geometry
4.1Angles, Lines & Triangles
4.2Polygons
4.5Circle Properties
4.6Trigonometry & Pythagoras’ theorem
4.7Mensuration of 2D Shapes
4.83D Shapes & Volume
5Vectors & Transformation Geometry
6Statistics & Probability
6.1Statistical Measures
6.2Graphical Representation of Data
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