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

Answer:

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