Lesson+1.1

// **Lesson 1.1: Evaluate Expressions** //

A variable is a letter used to represent one or more numbers. The numbers are the values of the variable. Expressions consist of numbers, variables, and operations. An algebraic expression, or //variable expression//, is an expression that includes at least one variable.


 * Algebraic expression || Meaning || Operation ||
 * 5(n) 5 × n 5n || 5 times n || Multiplication ||
 * __14__ 14 / yy || 14 divided by y || Division ||
 * 6 + c || 6 plus c || Addition ||
 * 8 - x || 8 minus x || Subtraction ||

Example 1:

Evaluate the expresion when x=3

a. 13/ //n// = 13⋅ 3

b. __9__ = __9__ n 3 = 3 Practice:

1) k+9 when k=7 2) 21-x when x=3 3) 1.5t when t=2.3 4) y-__3__ when y=__7__ 8 12