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HOW TO FACTOR WITH TI89 CALCULATOR

Option 1: Using a function typed into y1
 
Steps Key Sequence Screens
1. Clear Stored Values in Variables Press 2nd, then F1
(to select F6)
  Press 1
(for Clear a-z)
  Press ENTER
(to Clear a-z)
2. Input Equation into Y1  
3. Quit Equation Editor Press 2nd, then ESC (for QUIT)
4. Select Factor Function Press F2 (for Algebra menu)
  Press 2 (for 'factor(')
5. Input Function Press y, then 1,
then (x), then )
6. Execute Press ENTER
NOTE: If the calculator returns numerical values, then make sure you perform step #1!
Option 2: Using Home Screen
 
Steps Key Sequence Screens
1. Select Factor Function Press F2 (for Algebra menu)
  Press 2 (for 'factor(')
2. Input Function  
3. Input Independent Variable Press 'comma" key, then x, then ')'
NOTE: The independent variable can be x, t, or some other variable – the variable you type here should match your function.
4. Execute Press ENTER
NOTE: The factor function can be used to combine fractions!
NOTE: The factor function can be used to simplify rational expressions!