M8N1(F) estimate square roots of postive numbers

A square root is the product of two of the same number mulipied together.
EX. 0, 4,9,16. 25. 36.49,  81 etc
To estimate the square of a postive number find the square roots that it is close. Then decide which square root it is closests to.
EX
The square root of 85
85 would be found between 81 and 100 but it is closer to 81. The square root of 81 is 9 so the best estimate would be 9 for the square root.