document.write( "Question 114385: Tickets to a school dance cost $4, and the projected attendance is 300 persons. It is further projected that for every $0.1 increase in ticket price, the average attendance will decrease by 5. At what ticket price will the receipts from the dance be $1218? \r
\n" ); document.write( "\n" ); document.write( "If there is more then one solution, separate your answers with commas . \r
\n" ); document.write( "\n" ); document.write( "So I've got the formula of:
\n" ); document.write( "(4+.10x)(300-5x)=1218
\n" ); document.write( ".50x2+10x-18=0
\n" ); document.write( "Now I'm stuck. Can someone please help? \n" ); document.write( "
Algebra.Com's Answer #83327 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
Tickets to a school dance cost $4, and the projected attendance is 300 persons. It is further projected that for every $0.1 increase in ticket price, the average attendance will decrease by 5. At what ticket price will the receipts from the dance be $1218?\r
\n" ); document.write( "\n" ); document.write( "If there is more then one solution, separate your answers with commas .
\n" ); document.write( ":
\n" ); document.write( "So I've got the formula of:
\n" ); document.write( "(4+.10x)(300-5x) = 1218
\n" ); document.write( ":
\n" ); document.write( "You got all the thinking part done ok
\n" ); document.write( ":
\n" ); document.write( ".50x2+10x-18=0
\n" ); document.write( "however, here you should have:
\n" ); document.write( "-.5x^2 + 10x - 18 = 0
\n" ); document.write( ":
\n" ); document.write( "It's easier to deal with if the coefficient of x^2 is +1;
\n" ); document.write( "Multiply equation by -2 and you have:
\n" ); document.write( "+x^2 - 20x + 36 = 0
\n" ); document.write( ":
\n" ); document.write( "This factors easily to:
\n" ); document.write( "(x-18)(x-2) = 0
\n" ); document.write( "x = +18, +2 as the increased ticket prices that has a revenue of $1218
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "When x = 18; Ticket price: 4 + 1.80 = $5.80
\n" ); document.write( "When x = 2: Ticket price: 4 + .2 = $4.20
\n" ); document.write( ":
\n" ); document.write( "We can confirm that using your original equation
\n" ); document.write( "x = 18,
\n" ); document.write( "(4 + 1.8) (300 - 90))
\n" ); document.write( "5.8 * 210 = 1218
\n" ); document.write( ":
\n" ); document.write( "Price of $2
\n" ); document.write( "(4 + .2)*(300 - 10)
\n" ); document.write( "4.2 * 290 = 1218 also
\n" ); document.write( ":
\n" ); document.write( "Did this help? you about had it on your own!
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