For example, suppose you wanted to take the square root of 85. You can observe that 9 squared is 81, so the answer is sort of 9, right? But that’s off by 4 (85-81=4).

Square root days happen only a few times in a century, and the man who brought the day fame is celebrating his sixth one.

Learning to calculate square roots quickly can make a huge difference in your maths exams. Whether you're doing algebra, geometry, or other topics, being fast and accurate with square roots gives ...