Question

Below is a graph of test scores in a math class. Determine if the Points earned for each Correct Answer is proportional or not proportional. Explain your answer.

Answer 1

The graph is proportional. It is a straight line through the origin.

The slope is the constant

slope is (120-30)/(20-5) =90/15 =6

y = 6x

Check:

y = 6*12 =72

y = 6*18 =108