- Choose a number.
- Add 2 to the number you chose.
- Add 3 to the original number you chose.
- Multiply your answers from the 2nd and 3rd steps.
- Label that answer A.
- Square the original number you chose.
- Multiply the original number you chose times 5.
- Add 6 + your answers from 6 and 7.
- Label that answer B.
- Are B and A the same? (They should be!) See if that would always be the case. Repeat these steps but choose X for your number. Can you show that they will always be equal?
After you try it yourself, you can scroll down to see this worked out.
- Choose a number. 12
- Add 2 to the number you chose. 12 + 2 = 14
- Add 3 to the number you chose. 12 + 3 = 15
- Multiply your answers from the 2nd and 3rd steps. 14 x 15 = 210
- Label that answer A. A = 210
- Square the original number you chose. 12 x 12 = 144
- Multiply the original number you chose times 5. 12 x 5 = 60
- Add 6 + your answers from 6 and 7. 6 + 144 + 60 = 210
- Label that answer B. B = 210
- Are B and A the same? Yes!
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