document.write( "Question 969971: Please help me solve this problem
\n" ); document.write( "the sequence is as follows
\n" ); document.write( "----- , 3 , 17
\n" ); document.write( "What is the first term?
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Algebra.Com's Answer #592668 by KMST(5328)\"\" \"About 
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\n" ); document.write( "Is there a commonly used pattern to your sequence?
\n" ); document.write( "Is 3 the second term, and 17 the third term?
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\n" ); document.write( "A sequence could have no rhyme or reason, such as
\n" ); document.write( "potato , 3 , 7, duck , 1 , chair .
\n" ); document.write( "However, in algebra class teachers like sequences made with some sort of pattern.
\n" ); document.write( "The sequences with the commonly used patterns are an arithmetic sequence or a geometric sequence.
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\n" ); document.write( "If it is an arithmetic sequence, then each term is the one before plus a fixed number, \"d\" .
\n" ); document.write( "That number \"d\" is called the common difference, because it is the difference between any two consecutive terms.
\n" ); document.write( "So, term number \"n%2B1\" , \"a%5Bn%2B1%5D\" ,
\n" ); document.write( "is related to the previous term,
\n" ); document.write( "term number \"n\"=\"a%5Bn%5D\",
\n" ); document.write( "by \"a%5Bn%2B1%5D=a%5Bn%5D%2Bd\"<--->\"d=a%5Bn%2B1%5D-a%5Bn%5D\"
\n" ); document.write( "for all natural number (counting number) values of \"n\" .
\n" ); document.write( "If 3 and 17 are the 2nd and 3rd terms respectively,
\n" ); document.write( "then the common difference between consecutive terms is
\n" ); document.write( "\"d-17-3=14\" .
\n" ); document.write( "Each term is \"14\" more than the one before.
\n" ); document.write( "\"a%5B2%5D=3\" , \"a%5B3%5D=17\" , \"d=14\" , and \"a%5B1%5D\" is the first term that we want to find.
\n" ); document.write( "From \"a%5Bn%2B1%5D=a%5Bn%5D%2Bd\" , for \"n=1\" , we get
\n" ); document.write( "\"a%5B1%2B1%5D=a%5B1%5D%2Bd\"--->\"a%5B2%5D=a%5B1%5D%2B14\"--->\"3=a%5B1%5D%2B14\"
\n" ); document.write( "so \"a%5B1%5D%2B14=3\"--->\"a%5B1%5D=3-14\"--->\"a%5B1%5D=-11\"
\n" ); document.write( "
\n" ); document.write( "If it is a geometric sequence, then each term is the one before times a fixed number, \"r\" .
\n" ); document.write( "That number \"r\" is called the common ratio, because it is the ratio between any two consecutive terms.
\n" ); document.write( "So, term number \"n%2B1\" , \"b%5Bn%2B1%5D\" ,
\n" ); document.write( "is related to the previous term,
\n" ); document.write( "term number \"n\"=\"b%5Bn%5D\",
\n" ); document.write( "by \"b%5Bn%2B1%5D=b%5Bn%5D%2Ar\"<--->\"r=b%5Bn%2B1%5D%2Fb%5Bn%5D\"
\n" ); document.write( "for all natural number (counting number) values of \"n\" .
\n" ); document.write( "If 3 and 17 are the 2nd and 3rd terms respectively,
\n" ); document.write( "then the common ratio between consecutive terms is
\n" ); document.write( "\"r=17%2F3\" .
\n" ); document.write( "Each term is \"17%2F3\" times the one before.
\n" ); document.write( "\"b%5B2%5D=3\" , \"b%5B3%5D=17\" , \"r=17%2F3\" , and \"b%5B1%5D\" is the first term that we want to find.
\n" ); document.write( "From \"b%5Bn%2B1%5D=b%5Bn%5D%2Ar\" , for \"n=1\" , we get
\n" ); document.write( "\"b%5B1%2B1%5D=b%5B1%5D%2Ar\"--->\"b%5B2%5D=b%5B1%5D%2817%2F3%29\"--->\"3=b%5B1%5D%2817%2F3%29\"
\n" ); document.write( "so --->\"b%5B1%5D%2817%2F3%29=3\"--->\"b%5B1%5D=3%2F%28%2817%2F3%29%29\"--->\"b%5B1%5D=3%283%2F17%29\"--->\"b%5B1%5D=9%2F17\"
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