The profit P (in dollars) from selling x calculators is P=25x (-10x + 250). How many calculators are sold when the profit is $425?

Okay, so this is what I came to. I think that you might need to look through the placement of the problem again and your x's, but other than that, here it is!

Step 1: Simplify both sides of the equation. 425 = - 250 x2 + 6250x

Step 2: Subtract - 250x^2+6250x from both sides. 425 - ( - 250 x2 + 6250x) = - 250 x2 + 6250x - ( - 250 x2 + 6250x) 250 x2 - 6250x + 425 = 0

Step 3: Use quadratic formula with a=250, b=-6250, c=425. x = - b ± √ b2 - 4a c 2a x = - (-6250) ± √ (-6250) 2 - 4 (250) (425) 2 (250) x = 6250± √38637500 500 x = 252 + 110 √15455 or x = 252 + - 1 10 √15455

Answer: x = 252 + 110 √15455 or x = 252 + - 1 10 √ 15455