
So the answer is 
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I used the log rules
y*log(x) = log(x^y)
log(x) + log(y) = log(x*y)
these rules apply to any log base (not just base 10).
The correct next step Amy could take is to factor (x^2 - 16) on the left side of the equation to yield (x + 4)(x – 4)(x + 2) = 0.
The equation is given as:

The possible next steps are:
1. Expand the equation as follows

2. Express x^2 -16 as a difference of two squares as follows

However, the correct step in this case is to factor x^2 - 16 as a difference of two squares to give 
This is so, because the question says Amy is trying to solve for variable x.
This step will ensure that she gets the possible values of x, unlike expanding the whole equation .
Hence, the correct next step is 
Read more about equations at:
brainly.com/question/7674413
For any quadrilateral to be a parallelogram
i) either both the pairs of opposite sides must be equal
ii) Both the pairs of opposite sides must be parallel
iii) Opposite pairs of angles must be equal
iv) Diagonals must bisect each other.
v) A pair of opposite sides must be parallel and equal
Here we are already given that AB || CD
So either we should be given that AD || BC
or we must be given that AB = CD
Here it is given AB = CD as an option.
So Option A) or the first option is the right answer that AB ≅CD is needed to prove ABCD is a parallelogram.