Pre-Algebra Review Topic Using Your Calculator with Signed Numbers Topic Index | Algebra Index | Regents Exam Prep Center
If your scientific calculator has the "change sign" key , you can use it to find the opposite of a number.
On most scientific calculators, this key is pressed AFTER the number is entered.
On most graphing calculators, this key is pressed BEFORE the number is entered.
Examples for scientific calculators:
Example (1):
push:
Example (2):
128 78 => -9984
Example (3):
10 6 => -4
, 
10 
15 
=> 38
78 