document.write( "Question 567832: the 15th term in an arithmetic sequence is 43 and the sum of the first 15 terms of the series is 120. Determine the first three terms of the series \n" ); document.write( "

Algebra.Com's Answer #366728 by solver91311(24713) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "The sum of an arithmetic sequence is given by:\r
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\r
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\n" ); document.write( "\n" ); document.write( "Where

is the number of terms,

is the first term,

is the last term, and

is the sum of

terms.\r
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\n" ); document.write( "\n" ); document.write( "Plug in the given values of

, and

and then solve for

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\n" ); document.write( "\n" ); document.write( "Once you have the value for

, you can use that to find

, the common difference because the

th term is given by:\r
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\r
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\n" ); document.write( "\n" ); document.write( "Plug in the values you know for

, and

, then solve for

.\r
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\n" ); document.write( "\n" ); document.write( "Finally, calculate:\r
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\r
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\r
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\n" ); document.write( "\n" ); document.write( "and\r
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\r
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\n" ); document.write( "\n" ); document.write( "John
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\n" ); document.write( "My calculator said it, I believe it, that settles it
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$\"The$

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