A11­1UsingVariablesWritingExpressions.notebook Algebra 1 Ch.1 Notes Page 9 P9 1­1 Using Variables and Writing Expressions September 02, 2015 Variables Variables are things that can CHANGE. They can be Letters or Symbols in a problem. Variables are just letters that take the place of numbers in a problem. X, Y, and Z are all Variables. 3x + 4y + 12z Aug 25­4:28 PM Aug 25­4:29 PM Writing Expressions Key Terms Sum, Difference, Product, Quotient, Is, Equals More than, Less than, Increased by, Decreased by, Etc... Write Expression for the following statements. 1. 3 more than a number 2. 1/2 of a number plus 2 3. 2 less than 7 times a number Aug 22­7:44 AM 1