document.write( "Question 460257: Tickets sold = -0.2x^2+12x+11
\n" ); document.write( "x=1 is the day tickets go on sale. Use the quadratic equation to determine the last day tickets will be sold. I replaced x with 1 in the equation above to determine 22.8 tickets were sold on day one, but I'm not sure that is correct. How do I find out the last day tickets were sold? Can you show the work so I can understand how to find the answers? Thanks so much. =) \n" ); document.write( "
Algebra.Com's Answer #315709 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
Tickets sold = -0.2x^2+12x+11
\n" ); document.write( "x=1 is the day tickets go on sale.
\n" ); document.write( " Use the quadratic equation to determine the last day tickets will be sold.
\n" ); document.write( " I replaced x with 1 in the equation above to determine 22.8 tickets were sold
\n" ); document.write( " on day one, but I'm not sure that is correct.
\n" ); document.write( ":
\n" ); document.write( "That is correct, but since you can't have a fraction of ticket is would be 23 ticket on day 1
\n" ); document.write( ":
\n" ); document.write( "How do I find out the last day tickets were sold?
\n" ); document.write( ":
\n" ); document.write( "That would be when the tickets sold = 0, this is quadratic equation that will
\n" ); document.write( "peak and then return thru 0
\n" ); document.write( ":
\n" ); document.write( " -0.2x^2 + 12x + 11 = 0
\n" ); document.write( "you will have to use the quadratic formula to find x
\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"
\n" ); document.write( "In this equation; a=-.2, b=12, c=11
\n" ); document.write( "\"x+=+%28-12+%2B-+sqrt%2812%5E2-4%2A-.2%2A11+%29%29%2F%282%2A-.2%29+\"
\n" ); document.write( ":
\n" ); document.write( "\"x+=+%28-12+%2B-+sqrt%28144-%28-8.8%29%29%29%2F%28-.4%29+\"
\n" ); document.write( "\"x+=+%28-12+%2B-+sqrt%28144%2B8.8%29%29%2F%28-.4%29+\"
\n" ); document.write( "\"x+=+%28-12+%2B-+sqrt%28152.8%29%29%2F%28-.4%29+\"
\n" ); document.write( "Two solutions
\n" ); document.write( "\"x+=+%28-12+%2B+12.33%29%2F%28-.4%29+\"
\n" ); document.write( "x = \".33%2F%28-.4%29\"
\n" ); document.write( "x = -.825, obviously this is not our solution
\n" ); document.write( "and
\n" ); document.write( "\"x+=+%28-12+-+12.33%29%2F%28-.4%29+\"
\n" ); document.write( "x = \"%28-24.33%29%2F%28-.4%29\"
\n" ); document.write( "x = +60.825 ~ 61 days for 0 tickets to be sold
\n" ); document.write( ":
\n" ); document.write( "You can substitute 60.825 for x in the original equation and prove it to yourself
\n" ); document.write( ":
\n" ); document.write( "Did this make sense to you? \n" ); document.write( "
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