Guys i need help! A computer can sort x objects in t seconds, as modeled by the function below:

t=0.007x²+0.003x

How many objects are required to keep the computer busy for exactly 9 seconds?

Round to the nearest whole object.

Question

Guys i need help! A computer can sort x objects in t seconds, as modeled by the function below:

t=0.007x²+0.003x



How many objects are required to keep the computer busy for exactly 9 seconds?

Round to the nearest whole object.

anonymous · Answer

put t = 9
9 = 0.007x^2 + 0.003x
0.007x^2 + 0.003x - 9 = 0

solve this for x -  use the quadratic formula