Square Root Tricks.\r For finding square root of complete squares, we must memorize the squares of numbers 1 to 9.\r Squares of 1 and 9 have 1 in the units place.\r Squares of 2 and 8 have 4 in the units place.\r Squares of 3 and 7 have 9 in the units place.\r Squares of 4 and 6 have 6 in the units place.\r Squares of 5 have 5 in the units place.\r We use these fs to find square roots.