2. Lesson Menu Main Idea and New Vocabulary Example 1:Estimate a Square Root Example 2:Real-World Example

3. Main Idea/Vocabulary Estimate square roots. irrational number

4. Example 1 Estimate a Square Root List some perfect squares. 1, 4, 9, 16, 25, 36, 49, 64, 81, 100,… 81 < 96 < 10096 is between the perfect squares 81 and 100. Estimate to the nearest whole number. 96 Find the square root of each number.

5. Example 1 So, is between 9 and 10. Since 96 is much closer to 100 than 81,the best whole number estimate is 10. Verify with a calculator. Estimate a Square Root Answer:The best whole number estimate for

6. Example 1 CYP A.11 B.12 C.13 D.14 Estimate to the nearest whole number.

7. Example 2 SURFACE AREA The side length s of a cube can be found using the formulas where S.A. is the surface area of the cube. Estimate the side length of a cube with a surface area of 180 square inches. Write the equation.

8. Example 2 Replace S.A. with 180. Estimate the value of. 30 is between the perfect squares 25 and 36.

9. Example 2 So, is between 5 and 6. Since 30 about halfway between 25 than to 26, the best estimate is 5.5 Find the square root of each number. Answer:The best estimate for the side length of the cube is 5.5 inches.

10. Example 2 CYP A.8 secondsC.2 seconds B.4 secondsD.0.5 second GRAVITY The formula represents the time t in seconds that it takes an object to fall from a height of h feet. Estimate the time it would take a ball dropped from a roof measuring 65 feet in height to hit the ground.