Which statement is true about the graphed lines?
a) only graph a represents a proportional relationship.
b) only graph b represents a proportional relationship.
c) graph a and graph b both represent a proportional relationship.
d) graph a and graph b both represent a non-proportional relationship.

OPTION B.

Step-by-step explanation:

For this exercise it is important to remember that:

1.  Proportional relationships have the following form:

Where "k" is the constant of proportionality.

2. The graph of  a proportional relationship is an straight line that passes through the origin.

Observe the picture attached.

You can identify that:

- Graph A is a straight lines that does not pass through the origin. This means that it does not represent a proportional relationship.

- Graph B is a straight lines that passes through the origin. This means that it represents a proportional relationship.

Therefore, only Graph B represents a proportional relationship.

gregory's graph is incorrect because it shows 2 inches of growth for each week when it should show 0.75 inches of growth each week.