Question

carries smartphone plan with stark mobile includes unlimited talk and text and a certain amount of data every month. if she uses additional data, she is charged more on her bill. this graph shows the relationship between the number of additional gigabytes of data carrie uses in a month, x, and the total amount (in dollars) of her bill, y. do x and y have a proportional relationship? yes no write an equation for the relationship between x and y. simplify any fractions. y =

Explanation:

Step1: Recall the condition for proportionality

For a proportional relationship, the graph should be a straight - line passing through the origin $(0,0)$. The line in the graph does not pass through the origin. So the answer to "Do $x$ and $y$ have a proportional relationship?" is no.

Step2: Find the slope and y - intercept to write the equation

The equation of a line is $y=mx + b$, where $m$ is the slope and $b$ is the y - intercept.
Pick two points on the line, say $(0,28)$ and $(7,50)$.
The slope $m=\frac{y_2 - y_1}{x_2 - x_1}=\frac{50 - 28}{7-0}=\frac{22}{7}$.
The y - intercept $b$ is the value of $y$ when $x = 0$. From the graph, when $x = 0$, $y=28$.
So the equation of the line is $y=\frac{22}{7}x + 28$.

Answer:

no
$y=\frac{22}{7}x + 28$