Officials begin to release water from a full man-made lake at a rate that would empty the lake in 20 weeks, but a river that can fill the lake in 30 weeks is replenishing the lake at the same time. How many weeks does it take to empty the lake? Express your answer as a fraction reduced to lowest terms, if needed.

Empty rate = 1/18 job/week

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Fill rate = 1/25 job/week

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Together rate: 1/x

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Equation:

rate - rate = together rate

1/18 - 1/25 = 1/x

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Multiply thru by 18*25x

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25x - 18x = 18*25

7x = 18*25

x = 64.29 weeks (time required to empty)

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Cheers,

the required function is .

step-by-step explanation:

from the given table it is noticed that the graph passing through (-3,7), (0,4), (3,1) and (8,-4).

it is a linear function because the value of y is decrease by one as the value of x increase by 1.

the slope of the function is

the slope of the function is -1 and the y-intercept is 4.

the slope intercept form is

where, m is slope and b is y-intercept.

therefore the required function is . the graph of this function is shown below.

35%

step-by-step explanation: