As you will see from the many links on this blog there are many high quality Mathematics resources available on the Internet. The collection here was inspired by a recent test taken by my Year 10 (ages 14-15) students. You can use these to explore many topics you study.

**Definitions
**There are many excellent reference materials online, see the

**reference page**on this blog.

You could look up expression, equation and formula in

**Jenny Eather’s dictionary**for example to help you understand the difference between these terms. On the subject of expressions, equations and formulae, a related term you should be familiar with is identity. You could use this

**glossary for teachers**to look it up.

**Calculations
**You can obviously use a calculator but if you don’t have one to hand you could use

**WolframAlpha**or one of the many online calculators available such as

**this one from Mathisfun**.

**Algebra
**To solve a quadratic equation using the formula try

**this calculator**from Math Warehouse.

You could also

**plot the graph**, note the roots where the curve intersects the x axis, ie where y=0.

WolframAlpha can always be used to check algebra, for example you may wish to check the solution to a pair of simultaneous equations.

Trial and Improvement is a method for solving equations that you cannot solve exactly.

The spreadsheet illustrations below show the solution of x^{3}−x = 50.

The spreadsheet used here is of the extensive collection on **Mike Hadden’s MathsFiles** site (Trial and Error1dp).

On the subject of Excel, you could use it to plot points and draw a graph; you could then fit a trend line as shown in the example below. Examining the numbers here you should recognise the powers of 2, we have ** y = 1000×2 ^{x}**.

**Geometry
**Mathisfun has many useful

**Geometry resources**for example you could explore quadrilaterals with

**this interactive**and this

**area calculation tool**allows you to check the area of several common shapes.

**Trigonometry** – you can use this right-angled triangle calculator by Joe Barta to check any trigonometric calculations. Simply enter the known values and state the accuracy required.

To calculate the area of a triangle if you know two sides and the included angle you could use this **WolframAlpha widget**.

Try **this widget** for the cosine rule.

**Communicating Mathematics online** can be tricky! An online whiteboard can be the answer, I have used **Scriblink** here:

(For other online whiteboard resources see **this post**)