Answer:
She can buy 3 pairs for $9.00 with $2.00 extra.
Step-by-step explanation:
14x - (2x - y) - y
14x + (-1(2x - y)) - y
14x + (-1(2x) - 1(-y)) - y
14x + (-2x + y) - y
14x + 1(-2x + y) - y
14x + 1(-2x) + 1(y) - y
14x - 2x + y - y
14x - 2x
12x
In the given graph, lets mark two points:
Let
and 
The slope of the line is given by:



The equation of the line is given by:






Therefore, the function equation represented by the graph is: 
The answer is A. product.