A computer can sort x objects in t seconds, as modeled by the function below:
t=0.007x^2 + 0.003x
How many objects are required to keep the computer busy for exactly 9 seconds?

I got 9, but I really need someone to check it for me!!

Question

A computer can sort x objects in t seconds, as modeled by the function below:
t=0.007x^2 + 0.003x
How many objects are required to keep the computer busy for exactly 9 seconds?

I got 9, but I really need someone to check it for me!!

anonymous · Answer

As you need t to be 9, take t = 9, nad then solve the quadratic equation to get the answer :)

anonymous · Answer

And it is not 9 objects. Its a decimal number which you need to use the quadratic formula to get.

anonymous · Answer

Use this to solve if you dont know. http://2.bp.blogspot.com/_9xX2yNGJA4E/TPm214sFVjI/AAAAAAAAADI/nVLP-mPhYCM/s1600/QuadraticFormula.JPG

amorfide · Answer

Let t=9 since t is time
rearrange for quadratic equation

use quadratic equation

(-0.003+-sqrt(0.003^2-4x0.007x-9))/2x0.007

I get x=35.6

anonymous · Answer

Thank you so much! @amorfide