Question

brian is buying gift bags for all of the students in his class. the graph shows the relationship between the number of bags and the cost of the bags. write an equation relating the number of bags, x, and the cost, y. cost ($) 10 7.50 5 2.50 0 gift bags x y

Explanation:

Step1: Find the slope

The slope $m$ of a line passing through two points $(x_1,y_1)$ and $(x_2,y_2)$ is given by $m=\frac{y_2 - y_1}{x_2 - x_1}$. Let's take the points $(4,5)$ and $(8,10)$. Then $m=\frac{10 - 5}{8 - 4}=\frac{5}{4}=1.25$.

Step2: Use the slope - intercept form

The slope - intercept form of a line is $y=mx + b$, where $m$ is the slope and $b$ is the y - intercept. Since the line passes through the origin $(0,0)$, $b = 0$. Substituting $m = 1.25$ into the equation, we get $y=1.25x$.

Answer:

$y = 1.25x$