Answer
$2x(5x+1)^{2}$
Work Step by Step
$ 50x^{3}+20x^{2}+2x=\qquad$ ... factor out the gcf, $2x$
$=2x(25x^{2}+10x+1)$
$=2x[(5x)^{2}+2\cdot 5x\cdot 1+1^{2}]$
we use the formula for the square of a sum,
$(a+b)^{2}=a^{2}+2ab+b^{2}$
= $2x(5x+1)^{2}$