document.write( "Question 831708: The 11th term of an arthmetric sequence is 57 and the sum of the first and fourth terms is 29. Determine the first 3 terms of the sequence
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Algebra.Com's Answer #501602 by hovuquocan1997(83)![]() ![]() ![]() You can put this solution on YOUR website! You have a formula to find any term in a arithmetic sequence and it is \n" ); document.write( "Term = a + d(n - 1) \n" ); document.write( "in which a is the first term and d is the difference between the terms, and n is the number of the term \n" ); document.write( "ok so we have 11th term is 57, the equation will be \n" ); document.write( "57 = a + d(11-1) \n" ); document.write( "a + 10d = 57 \n" ); document.write( "That's the first equation \n" ); document.write( "Now we move to the second one \n" ); document.write( "We have First term is just \"a\" \n" ); document.write( "and fourth term is a+d(4-1) = a + 3d \n" ); document.write( "We have the sum of first and fourth terms is 29, that means a + a + 3d = 29 \n" ); document.write( "2a + 3d = 29 \n" ); document.write( "That's the second equation, now we have a system of 2 equations to solve for a, d \n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Now you know that a = 7, meaning that the first term is 7 \n" ); document.write( "d is 5, so the second term is 12, and the third term is 17 \n" ); document.write( "So the answer is 7, 12, 17 \n" ); document.write( "TA-DAH \n" ); document.write( ":D \n" ); document.write( " |