Casio FX-9750G PLUS User's Manual & Technical Reference page 463

6. Wipe off the surfaces of a new battery with a soft,
dry cloth. Load it into the calculator so that its positive
(+) side is facing up.
7. Install the memory protection battery cover onto the
calculator and secure it in place with the screw.
Next, replace the back cover.
8. Turn the calculator front side up and remove its case. Next, press o to turn
on power.
k k k k k About the Auto Power Off Function
Calculator power turns off automatically if you do not perform any key operation
for about 6 minutes. To restore power, press o.
Appendix B
Power Supply
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