The graph below represents the price of sending text messages using the services of a phone company. what is the constant of proportionality? a. 12 b. 24 c. 46. d. 48

Ah, direct variation/proportion.
That is simply a linear equation with a y-intercept of 0.
So... let's solve this.
Simply put, a direct variation multiplies the x-value by a constant to get the y-value.
Let's take the point on this graph and solve for the constant of proportionality:

We easily solve that and get our answer of . (B)

The answer is