document.write( "Question 350065: A book loaned out #250,000, part of it at the rate of 8% annual mortgage interest and the rest at the rate of 18% annual credit card interest. The interest received on both loans totaled $23,000. How much was loaned at each rate? \n" ); document.write( "
Algebra.Com's Answer #250271 by Theo(13342)\"\" \"About 
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Amount of money lent out totals $250,000\r
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\n" ); document.write( "\n" ); document.write( "x was loaned at 8% annual compounding assumed.
\n" ); document.write( "y was loaned at 18% annual compounding assumed.\r
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\n" ); document.write( "\n" ); document.write( "Interest received on both loans totaled $23,000 for the year.\r
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\n" ); document.write( "\n" ); document.write( "You have 2 formulas to work with.\r
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\n" ); document.write( "\n" ); document.write( "x + y = 250,000 covers the amount of the loan.
\n" ); document.write( ".08*x + .18*y = 23,000 covers the interest earned for the year.\r
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\n" ); document.write( "\n" ); document.write( "Solve both of these equations simultaneously and you will find how much was loaned out at each rate.\r
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\n" ); document.write( "\n" ); document.write( "Use first equation to solve for y.\r
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\n" ); document.write( "\n" ); document.write( "You get y = 250,000 - x\r
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\n" ); document.write( "\n" ); document.write( "Substitute in second equation to get:\r
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\n" ); document.write( "\n" ); document.write( ".08 * x + .18 * y = 23,000 becomes:\r
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\n" ); document.write( "\n" ); document.write( ".08 * x + .18 * (250,000 - x) = 23,000\r
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\n" ); document.write( "\n" ); document.write( "Simplify to get:\r
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\n" ); document.write( "\n" ); document.write( ".08 * x + .18 * 250,000 - .18 * x = 23,000\r
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\n" ); document.write( "\n" ); document.write( "Simplify further to get:\r
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\n" ); document.write( "\n" ); document.write( ".08 * x + 45,000 - .18 * x = 23,000\r
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\n" ); document.write( "\n" ); document.write( "Subtract 45,000 from both sides of the equation and combine like terms to get:\r
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\n" ); document.write( "\n" ); document.write( "-.1 * x = -22,000\r
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\n" ); document.write( "\n" ); document.write( "Divide both sides of the equation by -.1 to get:\r
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\n" ); document.write( "\n" ); document.write( "x = 220,000\r
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\n" ); document.write( "\n" ); document.write( "This means y = 30,000 because x + y = 250,000\r
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\n" ); document.write( "\n" ); document.write( "The book loaned 220,000 at 8% and 30,000 at 18% to make a total interest of 17,600 + 5,400 = 23,000 for the year.\r
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