Answer
$-6xy^{3}+5x^{2}y^{2}-x^{3}y+5x^{4}$
Work Step by Step
$-x(6y^{3}-5xy^{2}+x^{2}y-5x^{3})=(-x)(6y^{3})+(-x)(-5xy^{2})+(-x)(x^{2}y)+(-x)(-5x^{3})=(-6xy^{3})+5x^{1+1}y^{2}+(-x^{1+2}y)+5x^{1+3}=(-6xy^{3})+5x^{2}y^{2}+(-x^{3}y)+5x^{4}=-6xy^{3}+5x^{2}y^{2}-x^{3}y+5x^{4}$