document.write( "Question 1087946: Find the first term & common difference if:
\n" ); document.write( "10th term is 35;15th terms is 55
\n" ); document.write( "2nd term is 56 ;12th term is 16
\n" ); document.write( "8th term is 4;18th term is -96
\n" ); document.write( "7th term is -25;2th term is -45 \n" ); document.write( "

Algebra.Com's Answer #702237 by ikleyn(52798) $\"\"$ $\"About$

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\n" ); document.write( "Find the first term & common difference if:\r
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\n" ); document.write( "\n" ); document.write( "1) 10th term is 35; 15th terms is 55
\n" ); document.write( "2) 2nd term is 56 ; 12th term is 16
\n" ); document.write( "3) 8th term is 4; 18th term is -96
\n" ); document.write( "4) 7th term is -25; 2th term is -45
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\n" ); document.write( "\n" ); document.write( "I will solve #1 only. Do the remaining cases following the same pattern.\r
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document.write( "1) 10th term is 35; 15th terms is 55.\r\n" );
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document.write( "   Between the 10-th and 15-th terms, there is the room for 5 (=15-10) common differences d.\r\n" );
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document.write( "   So,  5d = 55 - 35 = 20.  Hence, d =  = 4.\r\n" );
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document.write( "   Thus you just found the common difference d = 4.\r\n" );
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document.write( "   Then from  =  + 9*d  you have\r\n" );
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document.write( "              =  - 9d = 35 - 9*4 = 35 - 36 = -1.\r\n" );
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document.write( "Answer.   = -1;  d = 4.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Make the remaining cases following this pattern.\r
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\n" ); document.write( "\n" ); document.write( "There is a bunch of lessons on arithmetic progressions in this site:\r
\n" ); document.write( "\n" ); document.write( "    - Arithmetic progressions\r
\n" ); document.write( "\n" ); document.write( "    - The proofs of the formulas for arithmetic progressions \r
\n" ); document.write( "\n" ); document.write( "    - Problems on arithmetic progressions \r
\n" ); document.write( "\n" ); document.write( "    - Word problems on arithmetic progressions\r
\n" ); document.write( "\n" ); document.write( "    - Mathematical induction and arithmetic progressions\r
\n" ); document.write( "\n" ); document.write( "    - One characteristic property of arithmetic progressions\r
\n" ); document.write( "\n" ); document.write( "    - Solved problems on arithmetic progressions \r
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\n" ); document.write( "\n" ); document.write( "Also, you have this free of charge online textbook in ALGEBRA-II in this site\r
\n" ); document.write( "\n" ); document.write( "    - ALGEBRA-II - YOUR ONLINE TEXTBOOK.\r
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\n" ); document.write( "\n" ); document.write( "The referred lessons are the part of this online textbook under the topic \"Arithmetic progressions\".\r
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