SOLUTION: An employee makes (3x-5) dollars am hour for x hours. If the employer wants to pay no more then 200 a day , what is the maximum number of hour the employee can work

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Question 968006: An employee makes (3x-5) dollars am hour for x hours. If the employer wants to pay no more then 200 a day , what is the maximum number of hour the employee can work
Answer by amarjeeth123(569) About Me  (Show Source):
You can put this solution on YOUR website!
We have (3x-5)x=200
3x^2-5x-200=0
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 3x%5E2%2B-5x%2B-200+=+0) has the following solutons:

x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac: b%5E2-4ac=%28-5%29%5E2-4%2A3%2A-200=2425.

Discriminant d=2425 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--5%2B-sqrt%28+2425+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%28-5%29%2Bsqrt%28+2425+%29%29%2F2%5C3+=+9.04071483483009
x%5B2%5D+=+%28-%28-5%29-sqrt%28+2425+%29%29%2F2%5C3+=+-7.37404816816342

Quadratic expression 3x%5E2%2B-5x%2B-200 can be factored:
3x%5E2%2B-5x%2B-200+=+3%28x-9.04071483483009%29%2A%28x--7.37404816816342%29
Again, the answer is: 9.04071483483009, -7.37404816816342. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+3%2Ax%5E2%2B-5%2Ax%2B-200+%29

The maximum number of hours is 9.07