document.write( "Question 977334: melissa invested a sum of money at 3% annual simple interest. she invested three times that sum of 5% annual simple interest. if her total yearly interest from both investments was $3600, how much was invested at 3%? \n" ); document.write( "
Algebra.Com's Answer #598867 by richwmiller(17219)\"\" \"About 
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Total yearly interest for the two accounts is: $3600
\n" ); document.write( "x=3y+0
\n" ); document.write( "0.05*x+0.03*y=3600
\n" ); document.write( "Substitute for x
\n" ); document.write( "0.05*(3y+0)+0.03*y=3600
\n" ); document.write( "Multiply out
\n" ); document.write( "0.15y+0+0.03*y=3600
\n" ); document.write( "Combine like terms.
\n" ); document.write( "0.15y+0+0.03*y=3600
\n" ); document.write( "0.15y+0.03*y=3600-0
\n" ); document.write( "0.18*y=3600
\n" ); document.write( "Isolate y
\n" ); document.write( "0.18*y=3600
\n" ); document.write( "y=3600/0.18
\n" ); document.write( "y=$20000 at 3%
\n" ); document.write( "y rounded off
\n" ); document.write( "y=$ 20000.00 at 3%
\n" ); document.write( "x=3y+0
\n" ); document.write( "x=3*20000+0
\n" ); document.write( "x=60000+0
\n" ); document.write( "x=$60000 at 5%
\n" ); document.write( "x rounded off
\n" ); document.write( "x=$ 60000.00 at 5%\r
\n" ); document.write( "\n" ); document.write( "x=$60000.00 at 5%
\n" ); document.write( "y=$20000.00 at 3%
\n" ); document.write( "Check
\n" ); document.write( "0.05*60000+0.03*20000=3600
\n" ); document.write( "3000+600=3600
\n" ); document.write( "3600=3600
\n" ); document.write( "If this statement is TRUE and neither x nor y is negative then all is well
\n" ); document.write( "codeinttm
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