Solving Equations

Algebra is all about balancing.

The word algebra comes from the Persian mathematician Abu Ja'far Muhammad ibn Musa Al‑Khwarizmi , who wrote a book titled Hisab al‑jabr w’al‑muqabala, meaning The Compendious Book on Calculation by Completion and Balancing.

The aim is to get the letter representing the unknown quantity {blob} by itself on one side of the equation.

To do this:

• Collect like terms
• Make {blob} the subject of the formula
• Divide by the coefficient of {blob}

Golden Rule

Inequalities are similar to equations – but do not use an equals sign.

A dashed line is put at x=12 to show that it is not included. The area shaded is the discarded bit that does not apply. (Sometimes done differently in other countries)

Sometimes, questions require solution sets.