document.write( "Question 52990This question is from textbook Intoductory Algebra
\n" ); document.write( ": Frank has half of his investments in stock paying an 11% dividend and the other half in a debentured stock paying 13% interest. If his total annual interest is $840, how much does he have invested.
\n" ); document.write( "Find the equation(s) and solve using substitution or elimination. \n" ); document.write( "
Algebra.Com's Answer #35347 by funmath(2933)\"\" \"About 
You can put this solution on YOUR website!
Let the amount he invested at 11%=x
\n" ); document.write( "Let the amount he invested at 13%=y
\n" ); document.write( "He invested the same amount in both stocks, so x=y
\n" ); document.write( "Interest(i)=principle(p)*rate(r)*time(t), but unless they specify that the time is different than one, i=p*r.
\n" ); document.write( "So the amount of interest he gets at 11%=.11x
\n" ); document.write( "The amount of interest he gets at 13%=.13y
\n" ); document.write( "Add the two together and your interest is=840
\n" ); document.write( "Therefore your system of linear equations is:
\n" ); document.write( "x=y
\n" ); document.write( ".11x+.13y=840
\n" ); document.write( "----------------Substitute the first equation into the second and you have:
\n" ); document.write( ".11x+.13(x)=840
\n" ); document.write( ".24x=840
\n" ); document.write( ".24x/.24=840/.24
\n" ); document.write( "x=$3,500 (the amount he invested at 11%)
\n" ); document.write( "y=x so y=$3,500 (the amount he invested at 13%)
\n" ); document.write( "Add the two investments together to find out how much he invested all together:
\n" ); document.write( "$3,500+$3,500=$7,000 is the amount he has invested altogether. \n" ); document.write( "
\n" );