1. Over Chapter 9 A.A B.B C.C D.D 5-Minute Check 1 A.10a 2 b 3 B.5 2 a 2 b 3 C.10ab 5 D.5ab 5 Write 5 ● 5 ● a ● a ● b ● b ● b using exponents.

2. Splash Screen

3. Then/Now You have already evaluated expressions containing squares of numbers. (Previous Course – Area of Squares!) Find square roots. Estimate square roots.

4. Vocabulary perfect square square root radical sign Rational number whose square root is a whole number (you get no decimal places). One of two equal factors of a number. The symbol √ used to indicate a nonnegative square root

5. Concept

6. Example 1 A Find Square Roots Answer: 8 A.

7. Example 1 B Find Square Roots Answer: –11 B.

8. Example 1 C Find Square Roots Answer: +16 and –16

9. Example 1 D Find Square Roots Answer: There is no square root because no number times itself is equal to –9. D.

10. A.A B.B C.C D.D Example 1 CYP A A.624 B.12.5 C.5 D.–5 A.

11. A.A B.B C.C D.D Example 1 CYP B A.12 B.–12 C.–72 D.–20,736 B.

12. A.A B.B C.C D.D Example 1 CYP C A.4 B.–4 C.4 and –4 D.256 and –256 C.

13. A.A B.B C.C D.D Example 1 CYP D A.–8 B.8 C.–32 D.There is no real square root. D.

14. Example 2 A Estimate Square Roots Answer: 5 A. The first perfect square less than 22 is 16. The first perfect square greater than 22 is 25.

15. B. Example 2 B Estimate Square Roots Answer: –18 The first perfect square less than 319 is 289. The first perfect square greater than 319 is 324.

16. A.A B.B C.C D.D Example 2 CYP A A.6 B.7 C.8 D.9 A.

17. A.A B.B C.C D.D Example 2 CYP B A.–6 B.–7 C.6 D.7 B.

18. Example 3 Use a Calculator to Estimate a Square Root Use a calculator. Round to the nearest tenth. Check for Reasonableness Since 8 2 = 64, the answer is reasonable.  ENTER2nd 577.549834435

19. Example 4 Use a Calculator to Estimate a Negative Square Root Use a calculator. Round to the nearest tenth. Check for Reasonableness Since 7 2 = 49, the answer is reasonable.  ENTER2nd 426.480740698

20. A.A B.B C.C D.D Example 3 A.3.9 B.9.8 C.38.5 D.There is no real square root.

21. A.A B.B C.C D.D Example 4 A.–8.5 B.–36.0 C.8.5 D.There is no real square root.

22. Example 5 Use Square Roots to Solve Problems SKYSCRAPER The tallest building in Houston, Texas, is the JP Morgan Chase Tower, standing at 1002 feet. About how far to the horizon can a person standing on the top floor see? Round your answer to the nearest tenth. Replace h with 1002. Evaluate the square root first. Write the formula.

23. Example 5 Use Square Roots to Solve Problems ≈ 38.6Multiply. Answer: On a clear day, a person could see about 38.6 miles.

24. A.A B.B C.C D.D Example 5 A.23.2 miles B.23.3 miles C.23.7 miles D.24.4 miles

25. End of the Lesson