Simplify 5s^6t^2+6st^9-8s^6t^2-6t^7

$5 s^{6} t^{2} + 6 s t^{9} - 8 s^{6} t^{2} - 6 t^{7}$

Subtract $8 s^{6} t^{2}$ from $5 s^{6} t^{2}$ .

$- 3 s^{6} t^{2} + 6 s t^{9} - 6 t^{7}$