Use the distributive property to remove the parentheses.
(10z^6-6z^4+3)7z^3
Simplify your answer as much as possible.
First distribute the 7z^3 to each term inside the parentheses:
7z^3 * 10z^6 - 7z^3 * 6z^4 + 7z^3 * 3
This simplifies to:
70z^9 - 42z^7 + 21z^3