The correct product should have been:
<span>(–4x + 9)2 = </span>(-4x)2 + 2(-4x)(9) + 9^2 = 16x6 - 72x +81
The result is a trinomial and not a binomial nor a difference of two squares.
So, the answer is:
C = Kylie did not understand that this is a perfect square trinomial, and she did not determine the product correctly.
When you cannot simplify it further. The terms have no common factor besides 1 and A plus C does not have two numbers that multiply to the total and equal C.
Let's use the equation 5x - 20 = 10 as an example for this.
To work backwards from this, you would add the same amount to each side.
You want to isolate the 5x so that you can solve for x.
To do that, you would add 20.
But again, you must add and subtract the same amount to both sides.
So it would look a bit like this:
5x - 20 + 20 = 10 + 20
That would simplify to 5x = 30, or in other words, x = 6.
Basically, you isolate the multiple of the variable then divide the answer to the equation from that multiple.
In the example, 5 is the multiple and after isolating it, the answer was 30.
30 ÷ 5 = 6
x = 6
Hope this helps :)