Square roots are a topic where mistakes can be easily made.
To try and define it in simple words lets say to ourselves:
"The square root of a number is what you would multiply by itself to reach this number."
e.g. If we are trying to find √81...
We should ask ourselves first:
"What do I multiply by itself to reach 81?"
The answer is 9.
So √81 = 9
Square roots of decimals
If you are ever asked to find the square root of a decimal without a calculator, it is much simpler to use a square number that you already know.
e.g. Find √1.21
We need to look for a square number that has the numbers 121 in that order.
We should notice that:
√121 = 11
Therefore, √1.21 must be 1.1
In this activity, you will find square roots of whole numbers and decimals without using a calculator.
When finding the square root of a decimal, you will need to relate it to a whole square number.