Please explain step by step.
(Good answers with good explanation only please.)
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Answer:
A
Step-by-step explanation:
x= total number of sets bought
y= total cost
Since each set costs 3 dollars, we can represent that with the equation y=3x, and the teacher also had a 2 dollar coupon, so we can subtract 2 from the equation, giving us y=3x-2
So, by looking at the charts, plug in x (the input), and see if the y (output) is the same as the equation represents.
So, the answer is A. To test, plug in the x and see if it gives the right y.
For example, 3 sets bought (x), so it will be represented as,
y=3x-2
y=3(3)-2
y=7
So when 3 is x, y is 7. Which is what answer choice A shows.