Answer
$y = \frac{-1}{4} x + 6$
Work Step by Step
From the chart, we are given the points $(0,6) (2, 5.5) (4,5)$
To determine the slope, use $m = \frac{y_{2}-y_{1}}{x_{2}-x_{1}}$
Using (0,6) and (4,5), $m = \frac{5-6}{4-0} = \frac{-1}{4}$
b (the y-intercept) is equal to 6 (from (0, 6))
Thus the equation is $y = \frac{-1}{4} x + 6$