How do you Plus square roots?

Answer 1

You can either use logarithmic tables, or trial and error.

With trial and error, you make a guess at what the square root might be, and then see how close you are to the number when you multiply the guess by itself.... say I'm looking for the square root of 12,345. I know that it must be more than 100 - because 100 x 100 = 10,000 so I can guess at 120 and see what 120 x 120 makes.

That turns out to be 14,400 - which is a bit high, so I can try halfway - 110 x 110 = 12,100.... so now I'm getting closer.

I can try like this to refine the number closer and closer to the desired number. 111 x 111 = 12,321... so I need to go to decimal places....

111.5 x 111.5 = 12432.25... still a but high, so I'll drop down to

111.2 x 111.2 That gives me 12365.44... so I need to go down more

111.1 x 111.1 = 12343.21 - now I'm getting really close.

Let's try 111.13 x 111.13... and so on, getting closer and closer all the time.