## Key Concepts

- The addition and multiplication properties of equality allow the same operation to be performed on both sides of an equation
- To solve an equation containing an absolute value, first isolate the absolute value then write two equations: [latex]|u| = c[/latex] and [latex]|u| = -c[/latex]
- Use the distributive property to eliminate parentheses in equations before collecting and combining like terms.
- Use the multiplication property of equality to eliminate fractions from equations by multiplying both sides by the LCD.
- Eliminate decimals from an equation by multiplying both sides by a sufficient factor of 10.
- Equations may have one unique solution, no solutions, or an infinite number of solutions.

## Glossary

**coefficient **a number multiplying a variable

**equation **a mathematical statement of equivalency between two expressions

**expression **groups of terms connected by addition or subtraction

**term** a single number, or variables and numbers connected by multiplication

**variable **a symbol that stands for an unknown quantity, often represented by letters such as [latex]x, y, [/latex] or [latex]z[/latex].