Evaluate: 5n^2+25n-250

Expression: $5n^{2}+25n-250$

Factor out common term $5:{\quad}5(n^{2}+5n-50)$

$=5(n^{2}+5n-50)$

Factor $n^{2}+5n-50:{\quad}(n-5)(n+10)$

$=5(n-5)(n+10)$