Simple Arithmetic Calculations In Alg Mode; Keying In Negative Numbers - HP 12C Platinum Owner's Handbook Manual

Algebraic Mode (ALG)
To select algebraic mode, press f[. When the calculator is in algebraic
mode, the ALG status indicator is lit.

Simple Arithmetic calculations in ALG mode

To calculate 21.1 + 23.8:
Keystrokes (ALG mode)
21.1+
23.8
}
Once a calculation has been completed:
pressing another digit key starts a new calculation, or
pressing an operator key continues the calculation.
Keystrokes (ALG mode)
77.35-
90.89}
65gr§12}
z3.5}
You can also do long calculations without pressing } after each intermediate
calculation: just press it at the end. The operators perform from left to right, in
the order you enter them.
Keying in Negative Numbers (Þ)
The Þ key changes the sign of a number.
To key in a negative number, type that number and then press Þ.
To change the sign of an already displayed number (it must be the
rightmost number), press Þ.
Keystrokes (ALG mode)
75Þ
§7.1}
Appendix B
Display
21.10
23.80
} completes the calculation.
44.90
Display
77.35
} completes the calculation.
–13.54
96.75
New calculation:
Calculates 96.75 ÷ 3.5
27.64
Display
Changes the sign of 75
–75
Multiplies –75 by 7.1
–532.50
175
×
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