The square root of 85 is 9.22, or to be exact 9.21954445729289. If you are unsure about working out the square root of a number, visit NumberPlanet.com where the answer will be worked out for you quickly and easily.

The square of a number is that number multiplied by itself. For example, the square root of 100 is 10 because 10 x 10 = 100. The square root of 25 is 5 because 5 x 5=25. Sometimes they are perfect, like in these examples but for the majority of the time they will not be whole ‘perfect numbers’, or integers, and there will be a series on numbers after the decimal, which is why a calculator is often needed to find the answer. 1, 4, 9, 16, 25, 36, 49, 64, 81, 100 are all ‘perfect squares’.

It is possible to find perfect squares or estimate squares without a calculator. First of all, you need to estimate and get as close as you can by finding two perfect square roots your number is between then divide your number by one of those square roots. Take the average of the result of step two and the root. Use the result of step two to repeat steps two and three until you have a number that is accurate enough for you.

The square of a number is that number multiplied by itself. For example, the square root of 100 is 10 because 10 x 10 = 100. The square root of 25 is 5 because 5 x 5=25. Sometimes they are perfect, like in these examples but for the majority of the time they will not be whole ‘perfect numbers’, or integers, and there will be a series on numbers after the decimal, which is why a calculator is often needed to find the answer. 1, 4, 9, 16, 25, 36, 49, 64, 81, 100 are all ‘perfect squares’.

It is possible to find perfect squares or estimate squares without a calculator. First of all, you need to estimate and get as close as you can by finding two perfect square roots your number is between then divide your number by one of those square roots. Take the average of the result of step two and the root. Use the result of step two to repeat steps two and three until you have a number that is accurate enough for you.