document.write( "Question 142993: Walt made an extra $9000 last year from a part-time job. He invested part of the money at a 9% annual rate of interest, and the rest at an 8% annual rate of interest. At the end of the year, he made a total of $770 in interest. How much was invested at 8%? \n" ); document.write( "
Algebra.Com's Answer #104056 by checkley77(12844)\"\" \"About 
You can put this solution on YOUR website!
.09X+.08(9,000-X)=770
\n" ); document.write( ".09X+720-.08X=770
\n" ); document.write( ".01X=770-720
\n" ); document.write( ".01X=50
\n" ); document.write( "X=50/.01
\n" ); document.write( "X=$5,000 FOR THE INVESTMENT @ 9%.
\n" ); document.write( "9,000-5,000=$4,000 INVESTED @ 8%.
\n" ); document.write( "PROOF:
\n" ); document.write( ".09*5,000+.08*4,000=770
\n" ); document.write( "450+320=770
\n" ); document.write( "770=770
\n" ); document.write( "
\n" ); document.write( "
\n" );