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Exit Ticket: At noon, a tank has a water depth of 9 in. After 3 hours, the depth was 8 inches. At 6pm, the depth was 7 inches. What is the initial value for the function? help will be appreciated.

User Aleida
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1 Answer

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Answer:

Explanation:

The straight line equation is:

y = m*x + b Where m is the slope of the line and b the intercept with y-axis, in our case y is the depth of the tank and x (time in lapsus of 3 hours).

The slope m = ( y₂ - y₁ ) / (x₂ - x₁)

We have point A ( 3 , 8 ) and point B ( 6 , 7 )

m = ( 6 - 3 ) / (7 - 8 ) m = -3

We see that each 3 hours time-depth decreases 1 in.

Then to find the depth at the beginning of x-axis

At noon 12 tank was 9 inches, three hours before at 9 in the morning the depth was 10 inches and:

9 in the morning 10

6 in the morning 11

3 in the midnight 12

12 in the night 13

Then 13 is the intercept with y-axis

then the equation is:

h = - 3*x + 13

Note x is time in lapsus of 3 hours

User Scott
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