document.write( "Question 914695: Billy wants to invest 15000$, some at 5% and the rest at 10% interest. If he wants 8% yield on his money, how much should be invested at each rate? \n" ); document.write( "

Algebra.Com's Answer #555247 by richwmiller(17219) $\"\"$ $\"About$

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0.08*15000=$1200 interest earned on $15000 at 8%
\n" ); document.write( "Total amount of money invested: $15000
\n" ); document.write( "x+y=15000,
\n" ); document.write( "Total yearly interest for the two accounts is: $1200
\n" ); document.write( "0.05*x+0.1*y=1200
\n" ); document.write( "x=15000-y
\n" ); document.write( "Substitute for x
\n" ); document.write( "0.05*(15000-y)+0.1*y=1200
\n" ); document.write( "Multiply out
\n" ); document.write( "750-0.05*y+0.1*y=1200
\n" ); document.write( "Combine like terms.
\n" ); document.write( "0.05*y=450
\n" ); document.write( "Isolate y
\n" ); document.write( "y=$ 9000.00 at 10% earns $900 interest
\n" ); document.write( "x=15000-y
\n" ); document.write( "Calculate x
\n" ); document.write( "x=$ 6000.00 at 5% earns $300 interest
\n" ); document.write( "Check
\n" ); document.write( "0.05*6000+0.1*9000=1200
\n" ); document.write( "300+900=1200
\n" ); document.write( "1200=1200
\n" ); document.write( "If 1200=1200 is TRUE and neither x nor y is negative then all is well
\n" ); document.write( "codeint1
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