Factor the expression completely. -81x^3-36x^5

To factor the expression completely, we need to find the greatest common factor (GCF) of the terms in the expression.<br /><br />The GCF of $-81x^{3}$ and $-36x^{5}$ is $-9x^{3}$.<br /><br />Now, we can factor out the GCF from each term:<br /><br />$-81x^{3} - 36x^{5} = -9x^{3}(11) - 9x^{3}(4x^{2})$<br /><br />Simplifying further, we have:<br /><br />$-81x^{3} - 36x^{5} = -9x^{3}(11 + 4x^{2})$<br /><br />Therefore, the factored form of the expression is:<br /><br />$-81x^{3} - 36x^{5} = -9x^{3}(11 + 4x^{2})$