Estimating square root

Please do watch my first ever slide share presentation especially to those students who love math. I hope you will learn from this.

1. Estimating square root

2. In order to estimate square roots you must first know your perfect square. A perfect square is the number you get when you multiply a number by itself.

3. For instance, 1 is a perfect square because 1x1 = 1 4 is a perfect square because 2x2 = 4 9 is a perfect square because 3x3 = 9

4. Recall some common perfect square numbers. = 1 = 36 = 121 = 256 = 4 = 49 = 144 = 289 = 9 = 64 = 169 = 324 = 16 = 81 = 196 = 361 = 25 = 100 = 225 = 400  

5. = ?  

6. = 9  

7. = ?  

8. = 6  

9. = ?  

10. = ? Since 27 is not a perfect square, we have to use a method to calculate it’s square root.  

11. N ot all numbers are perfect squares. Not every numbers has an integer for a square root. W e have to estimate square roots for numbers between perfect squares.

12. To calculate the square root of a non-perfect square Place the values of the adjacent perfect squares on a number line. Interpolate between the points to estimate to the nearest tenth.

13. Example 1 : Estimate What are the perfect square on each side of 27? 25 30 31 35 36   One perfect square that is less and one that is greater. Mark the perfect squares 25 and 36 5x5 6x6

14. Estimate to the nearest tenth half 5 6 25 30 31 35 36 27 Estimate = 5.2   If we look at 27 on the number line we see that is closer to the perfect square 25. we figure out that the middle is between 30 and 31(30.5). This tells us that the square root of 27 is closer to 5 than 6.

15. Estimate : = 5.2 Check : (5.2) (5.2) = 27.04  

16. Example 2 : Find the perfect square smaller and larger than the given number. = ?  

17. Take the square root. smaller larger is between 8 and 9  

18. Example 3 : Between what two consecutive integers the square root of the number can be found? between 5 and 6