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Polynomial in standard form. (9b-1)(9b+1)

User RedKing
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2 Answers

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Answer:

81b^2 - 1

Explanation:

User Keren
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You have to use the method of FOIL (first, outer, inner and Last)

9b*9b is first

9b*1 is outer

-1*9b is inner

-1*1 is last

Together, they form the expression 81b^2 + 9b - 9b - 1

Collect like terms and the answer is 81b^2 - 1
User Viral Parmar
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