Question 16548
First take out the common factor of 4:
{{{100x^4-16y^4}}}
{{{4(25x^4 - 4y^4) }}}


Next notice the difference of squares, since {{{25x^4}}} and {{{4y^4}}} are perfect squares.  It factors like this:
{{{4(5x^2- _____)*(5x^2+ _____)}}}



{{{4(5x^2-2y^2)*(5x^2+ 2y^2)}}}


R^2 at SCC