Answers:
Slope = -900
Interpretation: The tank is losing 900 gallons of water per month
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Explanation:
We see that the two points (0,9000) and (10,0) are on the diagonal line
Apply the slope formula
m = (y2 - y1)/(x2 - x1)
m = (0-9000)/(10 - 0)
m = -9000/10
m = -900
The slope is -900
An alternative way to find the slope is to use the hints given by your teacher. You'll divide the two legs of the triangle and you should get -900. Don't forget to make the slope negative.
The negative slope indicates the line goes downhill as we move from left to right, which matches what the graph shows.
A negative slope means the y value goes down as x goes up.
More specifically, the water in the tank goes down as the time value goes up.
The tank is losing 900 gallons of water per month. This is because x is in months and y is in gallons.
