Brayden is simplifying the expression 4n – (n – 3)2. He begins by distributing the negative to the terms inside the parentheses. What should he have done instead?

Question

asked Aug 5, 2020 156k views

2 Answers

BSeitkazin · Answer 1 · 2020-08-10T20:16:20+0000

Answer: Square the binomial.

Explanation:

1. The form
(a+b)^(2) indicates that he must square the binomial.

2. By definition, the square of a binomial produces a trinomial, which has the following form:

$(a+b)^(2)=a^(2)+2ab+b^(2)\\(a-b)^(2)=a^(2)-2ab+b^(2)$

3. Then, you have:

4n-(n-3)^(2)=4n-(n^(2)-2(n)(3)+3^(2))=4n-(n^(2)-6n+9)=4n-n^(2)+6n-9=-n^(2)+10n-9

4. Therefore, the answer is the second option.