Answer
$20\sqrt 2$
Work Step by Step
Step 1: $\sqrt 50 + 5\sqrt 18$
Step 2: $\sqrt (2\times25) + 5\sqrt (2\times9)$
Step 3: $\sqrt 2\sqrt 25 + 5\sqrt 2\sqrt 9$
Step 4: $5\sqrt 2 + 5\sqrt 9\sqrt 2$
Step 5: $5\sqrt 2 + (5\times3)\sqrt 2$
Step 6: $5\sqrt 2 + 15\sqrt 2$
Step 7: $20\sqrt 2$
