Reuse an earlier result

Send a result from History back into the calculator so you can build on it.

You do not have to retype a long answer. The Use button in History types it into the calculator for you, exactly as if you had pressed the keys.

Open History from the top bar.
Find the entry you want. Tap Use under it. The result is typed into the calculator and, on a narrow screen, the History sheet closes so you can carry on.
Keep going: add an operator and more numbers, or use the result inside a bigger expression, then finish the calculation as usual.
If a message says "This calculator can't accept typed input", the current model cannot take text from outside. Press the keys yourself instead.

Tips

Use sends the result, not the whole calculation. To reuse the full line, tap Copy as, copy it, and then type or paste it where you need it.
For your most recent answer you can also use the answer key on the calculator itself. See the reuse last answer guide.