document.write( "Question 173563: Suppose you have a lemonade stand, and when you charge $1 per cup of lemonade you sell 50 cups. But when you raise your price to $2 you only sell 25 cups. Write an equation for the number of cups you sell as a function of the price you charge. Denote \"C\" for number of cups, and \"P\" for the price you charge. Assume the function is linear.\r
\n" ); document.write( "\n" ); document.write( "My try at it:
\n" ); document.write( "1P = C50
\n" ); document.write( "2P = C25 \n" ); document.write( "

Algebra.Com's Answer #128432 by Mathtut(3670) $\"\"$ $\"About$

You can put this solution on YOUR website!
we have 2 points we will label then (P,C) (1,50) and (2,25) so lets find the slope....change in C over change in P
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\n" ); document.write( "25-50/2-1=-25 which is the slope of our equation...now lets the point slope formula ...I am going to use point (2,25)
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\n" ); document.write( "C-25=-25(P-2)
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\n" ); document.write( "C-25=-25P+50
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\n" ); document.write( " $\"highlight%28C=-25P%2B75%29\"$
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\n" ); document.write( "as you can see this can also be solved for P
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\n" ); document.write( "divide all terms by -25
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\n" ); document.write( " $\"-C%2F25=P-3\"$
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\n" ); document.write( " $\"P=-C%2F25%2B3\"$
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