Vocabulary Terms

The following terms are used in the Ballpark Costs activity.  Please consider reviewing or presenting them to your students.

variable: A letter used to represent an unknown amount.

expression: This is a math sentence.  It can be a single variable. It can also be a combination of variables, numbers, and operation symbols.  Expressions show math relationships.

Examples of expressions include y, 4 + x, 
x2 - 5, 5r + 8t.

equation: A math sentence that shows two expressions are equal.  An equation will always have an equal sign included.   

Example: the equation t + 5 = 7t means that the expression t + 5 has the same value as 7t. 

evaluate: This means to find the value of an expression.  This can be done by substituting numbers for variables. 

simplify: To make the expression or equation easier.  This is done by combining like terms or applying properties. 

Example: The expression 5y –4 is the simpler version of 7y + 6 – 10 – 2y because 7y – 2y is 5y and 6 – 10 is –4.

solve: To find the number that makes the equation true.

solution: The number that makes the equation true.  The solution of 4x = 12 is x = 3.