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 q? I g
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-> 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 q? I g
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Question 1043584: 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 q? 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? Found 2 solutions by ikleyn, Edwin McCravy:Answer by ikleyn(52781) (Show Source):
Apparently you made a mistake with the quadratic formula:
x = -3q2+150q
substitute 150 for x
150 = -3q2+150q
Get 0 on the right side:
3q2-150q+150 = 0
To make it easier to solve, divide every
term on both sides by 3 -- since you can!:
q2-50q+50 = 0
a=1, b=-50, c=50
and and
Both answer are correct, so give them both. You should
try to find out where you went wrong, so that you won't
make the same mistake in other problems.
Edwin
