Answer
$13440x^4y^6$
Work Step by Step
According to the Binomial Theorem we can obtain the $r+1$th term of the expansion of the binomial $(x+y)^n$ by the formula $_nC_rx^{n-r}y^r$.
Hence here it is: (by plugging in $n=10,r=6$ and $x,2y$: $_{10}C_{6}(x)^{10-6}(2y)^{6}=210\cdot x^{4}64y^{6}=13440x^4y^6$
