Math

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To Reiny:
Hi, thank you for your time Reiny and your info. I am so sorry but on the first one I accidentally put 0 where I should have put =9. In other words, the first equation should have said (9n+1)squared =9. Really sorry to have taken up your time with the wrong equation, but if you are able to help me out again, with the right one, I would appreciate it. Also, I am unfamiliar with the sign you use that looks like a check mark, could you please advise what the sign means? Thanks for your help!

• Math -

(9n+1)squared = 9
We expand the term with the square:
(81n^2 + 18n + 1) = 9
81n^2 + 18n + 1 - 9 = 0
81n^2 + 18n - 8 = 0
Factoring,
(9n + 4)(9n - 2) = 0
n = -4/9 and n = 2/9
Note that there are two values of n.

The sign that looks like a check mark in #2 is a squareroot sign.

I'm not Reiny but I hope you can trust my answer.
Hope this helps :3

• Math -

(9n+1)^2 = 9

9n + 1 =-+ 3

9n +1 = -3

9n. = -4

n = -4/9

9n + 1 = 3

9n = 2
n = 2/9

-4/9, 2/9

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