Estimating Square roots:

 Place √4 , √16, √25 on the number line

 Now place √18 and √5 on the number line. How did you know where to place it?

This is the number line method to find the square root of 18.

You estimate the square roots of numbers that are not perfect squares. You are to make a reasoned guess that is close to the actual value, without calculating it exactly.

We can often find a better estimate of a square root by writing the square root to more decimal places. For example, we can estimate 5 to be 2.2 to the nearest tenth, 2.24 to the nearest hundredth, 2.236 to the nearest thousandth, and so on.