Solving Linear Equations (Edexcel IGCSE Maths A)

The greatest power of in a linear equation is 1.

There is no term in x² or any higher power.

Isolate the variable means to get the variable term, e.g. , by itself on one side of the equation.

Inverse operations are the opposite operations to what has already happened to the variable.

E.g. In the expression , is being multiplied by 4.
The inverse operation is to divide by 4.

Examples of inverse operations are:

• Add and subtract

• Multiply and divide

• Square and take the square root

True.

To solve a linear equation, you need to isolate the variable, (get the letter on its own), by carrying out inverse operations to both sides.

E.g.

To solve a linear equation of the form :

• First subtract from both sides

• Then divide both sides by

True.

If a linear equation contains the unknown variable on both sides, you should first collect the variable terms on one side.

E.g.

The first step to solve a linear equation with brackets is to expand the brackets (on both sides if necessary).

E.g.

The first step to solve a linear equation with fractions is to remove the fractions by multiplying both sides by the denominators.

E.g.

After solving a linear equation, you should substitute your answer back into the equation to check if it is correct.

This is a quick way to spot if you have made any mistakes.