SOLUTION: I am given a table that states: TIme in Minutes Tub Has Been Draining, X: (3 then 5) Depth in Water in Tub in Inches, Y: (18 then 12) The question is: How dee

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: I am given a table that states: TIme in Minutes Tub Has Been Draining, X: (3 then 5) Depth in Water in Tub in Inches, Y: (18 then 12) The question is: How dee      Log On


   



Question 366853: I am given a table that states:
TIme in Minutes Tub Has Been Draining, X: (3 then 5) Depth in Water in Tub in Inches, Y: (18 then 12)
The question is:
How deep was the water before the drain was opened?
I have tried to solve by finding the rate which I think is 6 inches per every 2 minutes. Please help! Thankyou

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
I am given a table that states:
TIme in Minutes Tub Has Been Draining, X: (3 then 5) Depth in Water in Tub in Inches, Y: (18 then 12)
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You have two points relating time and depth: (3,18) and (5,12)
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slope = (depth change)/(time change) = (18-12)/(3-5) = -6/2 = -3 inches per unit of time
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Equation Form: depth = m(time)+b
Using (5,12) and m = -3, solve for "b":
12 = -3(5) + b
b = 27
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Equation:
d = -3t + 27
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The question is:
How deep was the water before the drain was opened?
d(0) = --3*0 + 27
d(0) = 27 inches (depth of the water when time = zero)
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Cheers,
Stan H.
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