document.write( "Question 379247: Find the fifth term of (7x+2y)^15\r
\n" ); document.write( "\n" ); document.write( "This is what I have so far. \r
\n" ); document.write( "\n" ); document.write( "(n)
\n" ); document.write( "(r) (a)^n-r(b)^r\r
\n" ); document.write( "\n" ); document.write( "a=7
\n" ); document.write( "b=2
\n" ); document.write( "n=15
\n" ); document.write( "r=4\r
\n" ); document.write( "\n" ); document.write( "15 nCR 4*(7)^11*(2)^4\r
\n" ); document.write( "\n" ); document.write( "The answer that the calculator gives you is 4.32^13. I am confused about what exponents I put for x and y since the solution of the equation has an exponent involved with it. Any help would be appreciated. Thanks! \n" ); document.write( "
Algebra.Com's Answer #269309 by robertb(5830)\"\" \"About 
You can put this solution on YOUR website!
To know the 5th term (starting from the LEFT), you must realize that counting of powers of 2y start at 0 (from the very first term, again from the left). Hence at the 5th term, the power of 2y must be 4.
\n" ); document.write( "This is your r in nCr. Thus by the binomial theorem, the 5th term must be
\n" ); document.write( " \n" ); document.write( "
\n" );