Question

the water level in a tank is changing at a constant rate. the graph shows the relationship between time in hours, x, and the water level in meters, y. complete the statement that describes the rate of change of the water level with respect to time.

Explanation:

Step1: Identify two points on the line

Let's take the points (0, 9) and (6, 7).

Step2: Use slope - formula

The slope formula is $m=\frac{y_2 - y_1}{x_2 - x_1}$. Here, $x_1 = 0,y_1 = 9,x_2=6,y_2 = 7$. So $m=\frac{7 - 9}{6-0}$.

Step3: Calculate the slope

$m=\frac{- 2}{6}=-\frac{1}{3}$.

Answer:

The water level is decreasing at a rate of $\frac{1}{3}$ meters per hour.