Answer:
-80x^6y
Step-by-step explanation:
[tex]-8x^3(10x^3y)\\\\\mathrm{Apply\:exponent\:rule}:\quad \:a^b\times\:a^c=a^{b+c}\\\\x^3x^3=\:x^{3+3}\\\\=-8\times\:10x^{3+3}y\\\\\mathrm{Add\:the\:numbers:}\:3+3=6\\\\=-8\times\:10x^6y\\\\\mathrm{Multiply\:the\:numbers:}\:8\times\:10=80\\\\=-80x^6y[/tex]
