Factor the following expression. \[ 30 v^{5} w^{9}+18 v w^{3} x^{8} \]

Step 1 ：Identify the common factors in both terms. The common factors are: the numerical factor: 6 and the variable factor: \(v w^{3}\).

Step 2 ：Factor out these common factors from the expression: \(30 v^{5} w^{9}+18 v w^{3} x^{8} = 6 v w^{3} (5 v^{4} w^{6} + 3 x^{8})\).

Step 3 ：\(\boxed{6 v w^{3} (5 v^{4} w^{6} + 3 x^{8})}\) is the factored form of the given expression.