document.write( "Question 646749: A city government has approved the construction of a $800 million sports arena. Up to $480 million will be raised by selling bonds that pay simple interest at a rate of 4% annually. The remaining amount (up to $640 million) will be obtained by borrowing money from an insurance company at a simple interest rate of 9%. Determine whether the arena can be financed so that the annual interest is $59 million. (If it is not possible, enter NONE for each answer.) \n" ); document.write( "
Algebra.Com's Answer #405934 by Theo(13342)![]() ![]() You can put this solution on YOUR website! x + y = 800 \n" ); document.write( "x <= 480 \n" ); document.write( "interest rate on x = .04 \n" ); document.write( "y <= 640 \n" ); document.write( "interest rate on y = .09 \n" ); document.write( ".04x + .09y = 59 \n" ); document.write( "x+y = 800 \n" ); document.write( "from x + y = 800, solve for y to get: \n" ); document.write( "y = 800 - x \n" ); document.write( "substitute for y in .04x + .09y = 59 to get \n" ); document.write( ".04x + .09(800-x) = 59 \n" ); document.write( "simplify to get: \n" ); document.write( ".04x + 72 - .09x = 59 \n" ); document.write( "combine like terms to get: \n" ); document.write( "-.05x + 72 = 59 \n" ); document.write( "subtract 72 from both sides of the equation to get: \n" ); document.write( "-.05x = -13 \n" ); document.write( "divide both sides of the equation by -.05 to get: \n" ); document.write( "x = 260 \n" ); document.write( "this makes y = 540 \n" ); document.write( "you have: \n" ); document.write( "x = 260 \n" ); document.write( "y = 540 \n" ); document.write( "x + y = 800 \n" ); document.write( ".04x + .09y = .04(260) + .09(540) = 10.4 + 48.6 = 59 \n" ); document.write( "that's your answer. \n" ); document.write( "260 million raised at 4% \n" ); document.write( "540 million raised at 9%. \n" ); document.write( "total annual interest = 59 million. \n" ); document.write( "interest is simple interest so the same amount of interest is payed out each year.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |