Another System of Equations?

Algebra Level 3

$\large{\\ \\ \begin{cases} { a }^{ 4 }+{ ( ab ) }^{ 2 }+{ b }^{ 4 }=900 \\ { a }^{ 2 }+ab+{ b }^{ 2 }=45 \end{cases}}$

Let $a$ and $b$ be real numbers that satisfy the equation above. Find the value of $2ab$ .