Answer
$-10y^{2}+y^{}$
Work Step by Step
Using the Distributive Property, the given expression, $
y^{5/8}(y^{3/8}-10y^{11/8})
,$ simplifies to
\begin{array}{l}\require{cancel}
y^{5/8}(y^{3/8})+y^{5/8}(-10y^{11/8})
\\\\=
y^{\frac{5}{8}+\frac{3}{8}}-10y^{\frac{5}{8}+\frac{11}{8}}
\\\\=
y^{\frac{8}{8}}-10y^{\frac{16}{8}}
\\\\=
y^{1}-10y^{2}
\\\\=
y^{}-10y^{2}
\\\\=
-10y^{2}+y^{}
.\end{array}
