1. Choose a number.
2. Add 2 to the number you chose.
3. Add 3 to the original number you chose.
4. Multiply your answers from the 2nd and 3rd steps.
5. Label that answer A.
6. Square the original number you chose.
7. Multiply the original number you chose times 5.
8. Add 6 + your answers from 6 and 7.
9. Label that answer B.
10. 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.

 

 

1. Choose a number.   12
2. Add 2 to the number you chose.   12 + 2 = 14
3. Add 3 to the number you chose.   12 + 3 = 15
4. Multiply your answers from the 2nd and 3rd steps.   14 x 15 = 210
5. Label that answer A.   A = 210
6. Square the original number you chose.   12 x 12 = 144
7. Multiply the original number you chose times 5.   12 x 5 = 60
8. Add 6 + your answers from 6 and 7.   6 + 144 + 60 = 210
9. Label that answer B.   B = 210
10. Are B and A the same? Yes!

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