document.write( "Question 1039313: Insert the indicated number of arithmetic means between the two given numbers \r
\n" ); document.write( "\n" ); document.write( "Three; a+2 and 5a-10 \r
\n" ); document.write( "\n" ); document.write( "So it looks like this \r
\n" ); document.write( "\n" ); document.write( "a+2 _ _ _ 5a-10\r
\n" ); document.write( "\n" ); document.write( "Find the three terms between them\r
\n" ); document.write( "\n" ); document.write( "Thank you please help me
\n" ); document.write( "Please with solution so i can study it myself
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Algebra.Com's Answer #654060 by KMST(5328)\"\" \"About 
You can put this solution on YOUR website!
ONE WAY TO GET TO THE ANSWER (Probably the expected way):
\n" ); document.write( "When you fill in the blanks, the five numbers (or expressions) form an arithmetic sequence.
\n" ); document.write( "\"a%5B1%5D=a%2B2\" is the firs term of the sequence.
\n" ); document.write( "\"a%5B5%5D=5a-10\" is the fifth element of the sequence.
\n" ); document.write( "In an arithmetic sequence each term is the one before plus a common difference, \"d\" .
\n" ); document.write( "In formulas, that is written as
\n" ); document.write( "\"a%5Bn%2B1%5D=a%5Bn%5D%2Bd\" , or \"a%5Bn%5D=a%5Bn-1%5D%2Bd\" .
\n" ); document.write( "As a consequence, any term is related to the first term, and the common difference by the formula
\n" ); document.write( "\"a%5Bn%5D=a%5B1%5D%2B%28n-1%29%2Ad\"
\n" ); document.write( "So, for \"n=5\" , \"a%5B5%5D=a%5B1%5D%2B%285-1%29%2Ad\" <---> \"a%5B5%5D=a%5B1%5D%2B4d\"
\n" ); document.write( "Since we know \"a%5B1%5D=a%2B2\" and \"a%5B5%5D=5a-10\" , we can substitute those expressions and solve for \"d\" :
\n" ); document.write( "\"5a-10=a%2B2%2B4d\" ---> \"5a-10-a-2=a%2B2-a-2%2B4d\" ---> \"4a-12=4d\" ---> \"%284a-12%29%2F4=d\" ---> \"d=a-3\" .
\n" ); document.write( "Now, we can find the missing terms:
\n" ); document.write( "The second term is
\n" ); document.write( "\"a%5B2%5D=a%5B1%5D%2Bd=a%2B2%2Ba-3=highlight%282a-1%29\" .
\n" ); document.write( "The third term is
\n" ); document.write( "\"a%5B3%5D=a%5B2%5D%2Bd=2a-1%2Ba-3=highlight%283a-4%29\" .
\n" ); document.write( "The fourth term is
\n" ); document.write( "\"a%5B4%5D=a%5B3%5D%2Bd=3a-4%2Ba-3=highlight%284a-7%29\" .\r
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\n" ); document.write( "\n" ); document.write( "ANOTHER WAY (This works only for sequences with an odd number of terms):
\n" ); document.write( "When three numbers are in an arithmetic sequence,
\n" ); document.write( "the middle term is the average of the first and last terms.
\n" ); document.write( "The same thing happens when in the sequence there are
\n" ); document.write( "5 terms, 7 terms, 9 terms, 11 terms, and so on.
\n" ); document.write( "So, the middle (third) term is
\n" ); document.write( "\"%28%28a%2B2%29%2B%285a-10%29%29%2F2%2B%286a-8%29%2F2=highlight%283a-4%29\" .
\n" ); document.write( "The second number, the one between \"a%2B2\" and \"3a-4\" is
\n" ); document.write( "\"%28%28a%2B2%29%2B%283a-4%29%29%2F2=%284a-2%29%2F2=highlight%282a-1%29\" .
\n" ); document.write( "The fourth number, the one between \"3a-4\" and \"5a-10\" is
\n" ); document.write( "\"%28%283a-4%29%2B%285a-10%29%29%2F2=%288a-14%29%2F2=highlight%284a-7%29\" .
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