in this video we're going to look at how you can estimate the square root of non-square numbers like here where we're being asked to estimate the square root of 77 the first step with questions like this is to find the two square numbers on either side of the number that you're given so if you need to find the square root of 77 you want to remember that 8 squared is 64 and 9 squared is 81 because 64 and 81 are the square numbers on either side of 77. and this tells us that the square root of 77 must be a number in between 8 and 9 so perhaps something like 8.5 however as 77 is closer to 81 than it is to 64 our answer will probably be closer to 9 than it is to 8. and so instead we might guess something like 8.8 which if we're only trying to give an answer to one decimal place is actually correct if we wanted to give it to three decimal places the answer would have been 8.775 but we can't really estimate to that level of detail let's try another one this time we're looking for the square root of 30. so we need to recall that 5 squared is 25 and 6 squared is 36 then because 30 is roughly in the middle of 25 and 36 we could estimate that our answer is roughly in the middle of five and six so maybe 5.5 which when given to one decimal place is the square root of 30. anyway that's everything for this video so if you found it useful then please do give us a like and subscribe and we'll see you again soon