Question

a school library starts a treasury with $20 from a donation and adds $5 for each book sold during a sale. write a linear function rule that represents the total amount of money in the treasury, y, after x books are sold.
slope-intercept form
$y = mx + b$
$y = ?x + $

Explanation:

Step1: Identify slope (m)

The amount added per book sold is $5, so the slope \( m = 5 \).

Step2: Identify y - intercept (b)

The initial amount (when 0 books are sold) is $20, so the y - intercept \( b = 20 \).

Step3: Write the linear function

Using the slope - intercept form \( y=mx + b \), substitute \( m = 5 \) and \( b = 20 \). So the function is \( y = 5x+20 \).

Answer:

\( y = 5x + 20 \) (The value in the green box is 5 and the value in the brown box is 20)