SOLUTION: The profit on a watch is given by P=x^2-13x-80 and where x is the number of watches sold her day. How many watches were sold on a day when there was a $50 loss?
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-> SOLUTION: The profit on a watch is given by P=x^2-13x-80 and where x is the number of watches sold her day. How many watches were sold on a day when there was a $50 loss?
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Question 167389: The profit on a watch is given by P=x^2-13x-80 and where x is the number of watches sold her day. How many watches were sold on a day when there was a $50 loss? Answer by nerdybill(7384) (Show Source):
You can put this solution on YOUR website! P=x^2-13x-80
How many watches were sold on a day when there was a $50 loss?
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This means P is -50.
Plug it in and solve for x:
P=x^2-13x-80
-50=x^2-13x-80
0=x^2-13x-30
factoring:
0=(x-15)(x+2)
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x = {-2, 15}
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We can toss out the negative answer so we get:
x = 15 watches
