Yes these numbers are a perfect square root because: Square root of 25 is 5 times 5 Square root of 36 is 6 times 6 Square root of 49 is 7 times 7 Square root of 64 is 8 times 8 Square root of 81 is 9 times 9 Square root of 100 is 10 times 10 HOPE THIS HELPS! ^_^