n^2-2n-3, where n is the number of key rings in thousands. Find the number of key rings sold on a particular day when the total profit is $5000

Question

I need to know what n stands for hen they make $5000

Answer 1

All righty then. You're going to solve for the roots of the polynomial here. And unless I miss my guess, only one of the two roots is going to be possible, or reasonable.

 

n^2 - 2n - 3 = 5000 or n^2 - 2n - 5003 = 0

 

You'll get two answers here. I'll apply the quadratic formula.

 

n = (2 +/- √20016) / 2 = 1 +/- 70.7= -69.7 or 71.7

 

Sure enough, one of those is not possible because you don't sell negative numbers of things. And the other one should be rounded off. You sold 72000 of... of... what were they again? LOL