Answer:
A
Explanation:
Lets first solve the relation for "y". Shown below:
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This is clearly an equation of a line in the form
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It will be a negatively sloped line, when graphed.
We can use vertical line test to determine function or relation. If a vertical line passes through only 1 point in the graph, we say that it is a function.
Think of a negatively sloped line. No matter where you draw a vertical line, it will only cut the line at 1 point.
So, this is definitely an equation of a function
Correct answer is A