Simplify the radical expression. solve it and tell me why

square root 405
(1 point)
Responses

5 times square root 9
Image with alt text: 5 times square root 9

9 times square root 5
Image with alt text: 9 times square root 5

negative 9 times square root 5
Image with alt text: negative 9 times square root 5

45

1 answer

3 times the square root of 45

This is because the square root of 405 can be simplified by factoring out the square of a perfect square number. 405 = 9 * 45, and the square root of 9 is 3. So, the square root of 405 is 3 times the square root of 45.