Question

Write the equation of the line that represents this graph. Show your work or explain how you determined the equations.

Answer 1

First the slope must be found.

The graph goes from (0,300) to (450,0), so the slope is falling by 300 every 450 units

numerically, the slope is

$\frac{ - 300}{450 }$

which simplifies to

$\frac{ - 2}{3}$

the y intercept is visible on the graph as 300, so now we plug in what we know to slope intercept form

y = (slope) x + y-intercept

$y = \frac{ - 2}{3} x + 300$