document.write( "Question 423912: to young college graduates opened a chain of stores in their home state. the chain expanded during the late 1990s and early 2000s and many new stores were opened. the number of stores in operation during any year from 1998 to 2008 is givin by the equation y= -2.5x to the second + 22.5x+50, where x is the number of years since 1998. how many more stores were in operation in 2004 that in 1999 ? \n" ); document.write( "

Algebra.Com's Answer #295577 by htmentor(1343) $\"\"$ $\"About$

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$\"+y+=+-2.5x%5E2+%2B+22.5x+%2B+50+\"$ , x = number of years since 1998.
\n" ); document.write( "In 1999, x = 1, so there were -2.5 + 22.5 + 50 = 70 stores
\n" ); document.write( "For 2004, x = 2004 - 1998 = 6 years.
\n" ); document.write( "Putting this into the equation gives -2.5*6^2 + 22.5*6 + 50 = 95 stores
\n" ); document.write( "Therefore, there were 95 - 70 = 25 more stores operating in 2004 than in 1999.
\n" ); document.write( "Note that the number of stores peaks at x = 4.5 years. After that the number of stores starts to decline.
\n" ); document.write( "At the end of the 10 years, they actually have less stores than when they started!
\n" ); document.write( "This is the graph of the equation:
\n" ); document.write( " $\"graph%28300%2C200%2C-20%2C20%2C-100%2C100%2C-2.5x%5E2%2B22.5x%2B50%29\"$ \n" ); document.write( "

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