Answer
$w=\pm 5i$
Work Step by Step
Step 1: $w^{2}+25=0$
Step 2: $w^{2}=-25$
Step 3: Using the square root property, $w=\pm\sqrt {-25}$.
Step 4: $w=\pm\sqrt {-1\times25}$
Step 5: $w=\pm\sqrt {-1}\times\sqrt {25}$
Step 6: $w=\pm i\times5$
Step 7: $w=\pm 5i$
