SOLUTION: I have worked out the quadratic equation for x= -3q^2+150q, where q is quantity. The question asks what is the quantity is if x = 150? So I'm basically being asked what is p? I g

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Question 1043586: I have worked out the quadratic equation for
x= -3q^2+150q, where q is quantity. The question asks what is the quantity is if x = 150? So I'm basically being asked what is p? I got:
q= 5(5 - radical 7) / 3 , q= 5(5 + radical 7) / 3
q=3.92375, q=12.74292.
But I don't know if that's the final answer to the question, or do I have to pick one of those two decimals?

Answer by ikleyn(52778) About Me  (Show Source):
You can put this solution on YOUR website!
.
I have worked out the quadratic equation for
x= -3q^2+150q, where q is quantity. The question asks what is the quantity is if x = 150?
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They ask you to solve this quadratic equation

150 = -3q%5E2+%2B+150q

for q. It is the same as quadratic equation 

3q%5E2+-+150q+%2B+150 = 0.

To solve it, divide both sides by 3. It is your first step. You will get an equivalent equation

q%5E2+-+50q+%2B+50 = 0.

Now apply the quadratic formula. You will get

q = %2850+%2B-+sqrt%2850%5E2+-+4%2A50%29%29%2F2 = %2850+%2B-+sqrt%282300%29%29%2F2 = %2850+%2B-+47.958%29%2F2 = . . . 

Please complete these calculations on your own.