document.write( "Question 981409: The 10th term of A.P is -5 and the 34th term is -57. Find the 15th term
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Algebra.Com's Answer #602395 by Timnewman(323)\"\" \"About 
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Hi,
\n" ); document.write( "Recall that the nth term of an A.P is giving by;T(n)=a+(n-1)d
\n" ); document.write( "where a=first term
\n" ); document.write( " d=commom difference.
\n" ); document.write( "Now, if 10th term is -5,
\n" ); document.write( "Therfore, a+9d=-5----(1)
\n" ); document.write( " also,if 34th term is -57,
\n" ); document.write( "then, a+33d=-57-----(2)
\n" ); document.write( "from equ (1),
\n" ); document.write( " a=-5-9d----(3)
\n" ); document.write( "substitute for a in equ (2)
\n" ); document.write( "i.e, -5-9d+33d=-57
\n" ); document.write( " 24d=-57+5
\n" ); document.write( "24d=-52
\n" ); document.write( "dividing bothsides by 24,
\n" ); document.write( "d=-13/6
\n" ); document.write( "put d in equ (1)
\n" ); document.write( " a=-5-9d
\n" ); document.write( "a=-5-9(-13/6)
\n" ); document.write( "a=-5+39/2
\n" ); document.write( "a=29/2
\n" ); document.write( "15th term(T(15)) =a+14d
\n" ); document.write( " but a=29/2
\n" ); document.write( " d=-13/6
\n" ); document.write( "15th term=(29/2)+14(-13/6)
\n" ); document.write( " =-95/6
\n" ); document.write( "You can put in mixed frction. \n" ); document.write( "
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