Question

how do I find the square root

Answer 1

a square root is basically just finding a number that, when multiplied by itself, equals your original number

Answer 2

For that, you don't need the exact square root. You need the approximate. The sqrt of 7 is between the sqrt of 4 and the sqrt of 9, but 7 is closer to 9, therefore the sqrt would be closer to 3. Find the approximate sqrt for 6 (between sqrt of 4 and sqrt of 9 again) and determine which sum is larger.