document.write( "Question 104636: Solve for R?\r
\n" ); document.write( "\n" ); document.write( "100=70/(1+R)+60/(1+R)^2 \n" ); document.write( "

Algebra.Com's Answer #76215 by Fombitz(32388) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"100=70%2F%281%2BR%29%2B60%2F%281%2BR%29%5E2\"$
\n" ); document.write( " $\"10%281%2BR%29%5E2=7%281%2BR%29%2B6\"$ Multiply both side by $\"%281%2BR%29%5E2%2F10\"$ .
\n" ); document.write( " $\"10%281%2B2R%2BR%5E2%29=7%281%2BR%29%2B6\"$ Expand.
\n" ); document.write( " $\"10%2B20R%2B10R%5E2=7%2B7R%2B6\"$ Distribute.
\n" ); document.write( " $\"10R%5E2%2B20R%2B10=7R%2B13\"$ Group terms on both sides.
\n" ); document.write( " $\"10R%5E2%2B13R-3=0\"$ Group terms on one side.
\n" ); document.write( " $\"R=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"$
\n" ); document.write( "where a=10, b=13, c=-3
\n" ); document.write( " $\"R=+%28-13%2B-+sqrt%28+13%5E2-4%2A10%2A%28-3%29+%29%29%2F%282%2A10%29+\"$
\n" ); document.write( " $\"R=+%28-13%2B-+sqrt%28+169%2B120%29%29%2F%2820%29+\"$
\n" ); document.write( " $\"R=+%28-13%2B-+sqrt%28+289%29%29%2F%2820%29+\"$
\n" ); document.write( " $\"R=+%28-13%2B-+17%29%2F%2820%29+\"$
\n" ); document.write( "First solution
\n" ); document.write( " $\"R=+%28-13%2B+17%29%2F%2820%29+\"$
\n" ); document.write( " $\"R=1%2F5\"$
\n" ); document.write( "Second solution
\n" ); document.write( " $\"R=+%28-13-+17%29%2F%2820%29+\"$
\n" ); document.write( " $\"R=+-3%2F2+\"$
\n" ); document.write( "Let's check one solution
\n" ); document.write( " $\"100=70%2F%281%2BR%29%2B60%2F%281%2BR%29%5E2\"$
\n" ); document.write( " $\"100=70%2F%286%2F5%29%2B60%2F%2836%2F25%29\"$
\n" ); document.write( " $\"100=350%2F6%2B250%2F6\"$
\n" ); document.write( " $\"100=600%2F6\"$
\n" ); document.write( " $\"100=100\"$
\n" ); document.write( "Good answer.
\n" ); document.write( "You can also check the other answer. \n" ); document.write( "

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