The constant of the proportional relationship graphed in this problem is of 10.
What is a proportional relationship?
A proportional relationship is a function in which the output variable is given by the input variable multiplied by a constant of proportionality, that is:
y = kx
In which k is the constant of proportionality.
In this problem, the points on the graph are: (0,0), (2,20), (4,40), ..., hence the constant is:
k = 40/4 = 20/2 = 10.
More can be learned about proportional relationships at https://brainly.com/question/10424180
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