Question

Kylie explained that (–4x + 9)2 will result in a difference of squares because (–4x + 9)2 = (–4x)2 + (9)2 = 16x2 + 81. Which statement best describes Kylie’s explanation?

Answer is C, (Kylie did not understand that this is a perfect square trinomial, and she did not determine the product correctly.)

Answer 1

the answer is correct because it would have to go like this;

(-4x + 9)² = (-4x + 9)(-4x + 9)

hope this helps, God bless!

Answer 2

In fact this equation:

`{(-4x+9)}^(2)` (1)

Is a perfect square trinomial, which is a polynomial of three terms that results from squaring a binomial (two terms); and the correct way to solve it is:

`{(a+b)}^(2)=a^(2)+2ab+b^(2)` (2)

Then, according to (2), the binomial (1) is solved as follows:

`{(-4x+9)}^(2)={(-4x)}^(2)+2(-4x)(9)+9^(2)`

`{(-4x+9)}^(2)=16x^(2)-72x+81` >>>>>>>This is the righ answer

Therefore, Kylie did not determine the product correctly