Equations Unit 2

1. EquationsUnit 2

2. Equation • Mathematical sentence with an equal sign. • Contains variables, numbers, and/or symbols • The sides of an equation are separated by an equal sign Example: 5x-1=9+x

3. Open Sentence • An equation that contains variables

4. Domain • A given set of numbers that are to be substituted in for the variable(s)

5. Solution Set • All solutions that make the equation true • We use braces for set notation • If not solution exists, we use { } or • Known as the empty set • All solutions that make the equation true • We use braces for set notation • If not solution exists, we use { } or • Known as the empty set

6. Example • Solve 5x-1=9 if • Read as “x belongs to the set whose numbers are 1, 2, and 3 • Steps used to solve this problem: • Create a table • Plug in values for the variable(s) • Simplify • If it is true, it is a solution; If it is false, not a solution