## Key Concepts

**Problem Solving Strategy for Geometry Applications**- Read the problem and make sure you understand all the words and ideas. Draw the figure and label it with the given information.
- Identify what you are looking for.
- Name what you are looking for. Choose a variable to represent that quantity.
- Translate into an equation by writing the appropriate formula or model for the situation. Substitute in the given information.
- Solve the equation using good algebra techniques.
- Check the answer in the problem and make sure it makes sense.
- Answer the question with a complete sentence.

**Properties of Circles**- \(d=2r\)
**Circumference:**\(C=2\pi r\) or \(C=\pi d\)**Area:**\(A=\pi {r}^{2}\)

## Glossary

### irregular figure

An irregular figure is a figure that is not a standard geometric shape. Its area cannot be calculated using any of the standard area formulas.