document.write( "Question 817320: the sum of the first two terms of a geometric series is 1 and the sum of its first four terms is 5. if all of its terms are positive, find the first term and the common ratio. \n" ); document.write( "
Algebra.Com's Answer #491984 by josgarithmetic(39620)\"\" \"About 
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a, ar, ar^2, ar^3, are the terms.\r
\n" ); document.write( "\n" ); document.write( "\"a%2Bar%2Bar%5E2%2Bar%5E3=5\"
\n" ); document.write( "\"a%28r%5E3%2Br%5E2%2Br%2B1%29=5\"
\n" ); document.write( "and
\n" ); document.write( "\"a%281%2Br%29=1\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "You might try multiplying the \"1\" equation by 5:
\n" ); document.write( "5a(r+1)=5*1
\n" ); document.write( "5a(r+1)=5
\n" ); document.write( "Not useful...\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "BETTER: You might try dividing the \"5\" equation's members by the \"1\" equation's members:
\n" ); document.write( "\"%28a%28r%5E3%2Br%5E2%2Br%2B1%29%29%2F%28a%281%2Br%29%29=5%2F1\"
\n" ); document.write( "\"highlight_green%28%28r%5E3%2Br%5E2%2Br%2B1%29%2F%28r%2B1%29=5%29\" and this equation should be useful. From this, try to simplify and use whatever polynomial handling skills you have, like rational roots theorem, remainder, factor theorems... \n" ); document.write( "
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