Divide 35b^5 +20ab^3 +20a^2b^2 by 5b^2

Basically, you just divide each term in the equation by b^2.
So 35b^5 / b^2 = 35b^3, 30ab^3 / b^2 = 30ab, and 20a^2b^2 / b^2 = 20a^2.
So your final answer is 35b^3 + 30ab + 20a^2.