A winery has a vat with two pipes leading to it. The inlet pipe can fill the vat in 4 hours, while the outlet pipe can empty it in 9 hours. How long will it take to fill the vat of both pipes are left open? (Explain work if at all possible.)

the correct answer is 45x

9×5=45 then add the x

if the eqn of the parabola is f(x) = (x-4)(x+2), we need to mult. this out to find the coordinates of the vertex.

then f(x) = x^2 + 2x - 4x - 8, and f(x) = x^2 - 2x - 8.

one way in which you can find the vertex is to calculate x = -b / (2a).   here, that comes to

        )

x = = 1.   f(1) = 1^2 - 2(1) - 8 = - 9.   vertex is at (1, -9).

        2(1) 

find another point on the curve:   let x=0, for which y=-8.   then (0, -8) is on the curve.   plot the vertex and this point and draw a smooth parabola thru both.

hope this

answer: no, but if it does it's a obvious pattern.

step-by-step explanation: