The equation in the function form is f(x) = -3x + 15 and the tub started with 15 gallons of water.
<h3>What is a function?</h3>
It is defined as a special type of relationship, and they have a predefined domain and range according to the function every value in the domain is related to exactly one value in the range.
We have an equation:
y –12 = –3(x – 1)
We can write the above equation as follows:
y = 12 - 3(x - 1)
y = 12 - 3x + 3
y = -3x + 15
or
f(x) = -3x + 15
Plug x = 0
f(0) = 15
The tub started with 15 gallons of water.
Thus, the equation in the function form is f(x) = -3x + 15 and the tub started with 15 gallons of water.
Learn more about the function here:
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