Answers:
a. Yes, it is proportional
b. y = (1/20)x
The slope 1/20 means that when the volume increase by 20 gallons the height increases by 1 inch.
c. 12.5 inches
Step-by-step explanation:
Part a.
The relation is proportional is the graph is a straight line that passes through the point (0, 0)
Since this graph satisfies this condition, the given relationship is proportional.
Part b.
The equation for a proportional relationship has the form
y = mx
Where m is the slope. Since the line passes through the point (20, 1), the slope is equal to
m = 1/20
So, the equation of the line is
y = (1/20)x
Where the slope 1/20 means that when the volume increase by 20 gallons the height increases by 1 inch.
Part c.
To know the height when the volume is 250 gallons, we need to replace x by 250, so
y = (1/20)x
y = (1/20)(250)
y = 12.5 inches
So, the height of the water will be 12.5 inches.