To find the equation of a line in slope-intercept form (y=mx+b) you follow the next steps:
1. Find the slope (m). Use two points in the line in the next formula:
![m=(y_2-y_1)/(x_2-x_1)](https://img.qammunity.org/2023/formulas/mathematics/high-school/78uaqhwt0aws3qfwxigaftpihnmb1gzxtp.png)
Points: (0,40) and (8,0)
![m=(0-40)/(8-0)=(-40)/(8)=-5](https://img.qammunity.org/2023/formulas/mathematics/college/6greto2fmip1ga0f6erxjwfceunebt5wxf.png)
2. Identify the yintercept: It is the value of the function when it cross the y-axis, or the value of the function when x=0
y-intercept in the given line is 40.
Then, you have the next equation in slope-intercept form for the given line:
![y=-5x+40](https://img.qammunity.org/2023/formulas/mathematics/college/ryiq821s4nfvtrr7tbkq7dqyr2ig9midqi.png)