The best and most correct answer among the choices provided by the question is the second choice "a right angle"
The formula for finding the slope of a line on a coordinate plane is (y2 - y1) / (x2 - x1), where (x2, y2) and (x1, y1) represent two distinct points on the line. This is also known as "change in y over change in x" or "rise over run."
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