Question

what method of factoring should first be used?
$7y^5 - 5z^3$
answer
greatest common factor
difference of perfect squares
trinomial factoring
none of the above

Explanation:

First, check for a greatest common factor (GCF) across the terms $7y^5$ and $-5z^3$. The coefficients 7 and 5 share no common factors other than 1, and there are no shared variables between the two terms. The expression is not a difference of perfect squares (it has no squared terms matching the form $a^2 - b^2$) nor a trinomial (it only has two terms). So none of the listed factoring methods apply initially.

Answer:

None of the Above