Problem 69 of 7
Use a polynomial identity for mental computation: 105^2-95^2.
Hints
Using a hint is okay. It just tells the trainer to give you a little more review.
Hidden until you reveal it.
rewrite numbers around convenient bases.
Hidden until you reveal it.
Choose an identity that simplifies arithmetic around a convenient base.
Enter your answer
No answer yet
Correct
Your answer is equivalent to the expected form.
Solution
Walkthrough
Walkthrough shown
Full solution stays hidden until you ask for it.
1. Rewrite numbers using a nearby convenient base.
2. Apply square, conjugate, or cube identity.
3. Compute simplified arithmetic.
Use the worked steps, then substitute the final answer back into the original relationship to confirm it satisfies the prompt.
Long arithmetic if identity selection is the task and no identity is used.