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1. 7-4 Division Properties of Exponents Warm Up Lesson Presentation Lesson Quiz Holt Algebra 1

2. Warm Up Simplify. 1.(x2)3 3. 5. 2. 4. 6. Write in Scientific Notation. 7. 8.

3. Objective Use division properties of exponents to evaluate and simplify expressions.

4. A quotient of powers with the same base can be found by writing the powers in a factored form and dividing out common factors. Notice the relationship between the exponents in the original quotient and the exponent in the final answer: 5 – 3 = 2.

6. Example 1: Finding Quotients of Powers Simplify. A. B.

7. Example 1: Finding Quotients of Powers Simplify. C. D.

8. Helpful Hint Both and 729 are considered to be simplified.

9. Check It Out! Example 1 Simplify. a. b.

10. Check It Out! Example 1 Simplify. c. d.

11. Simplify and write the answer in scientific notation Write 0.5 in scientific notation as 5 x 10 . Example 2: Dividing Numbers in Scientific Notation Write as a product of quotients. Simplify each quotient. Simplify the exponent. The second two terms have the same base, so add the exponents. Simplify the exponent.

12. Writing Math You can “split up” a quotient of products into a product of quotients: Example:

13. Simplify and write the answer in scientific notation. Write 1.1 in scientific notation as 11 x 10 . Check It Out! Example 2 Write as a product of quotients. Simplify each quotient. Simplify the exponent. The second two terms have the same base, so add the exponents. Simplify the exponent.

14. The Colorado Department of Education spent about dollars in fiscal year 2004-05 on public schools. There were about students enrolled in public school. What was the average spending per student? Write your answer in standard form. Example 3: Application To find the average spending per student, divide the total debt by the number of students. Write as a product of quotients.

15. The Colorado Department of Education spent about dollars in fiscal year 2004-05 on public schools. There were about students enrolled in public school. What was the average spending per student? Write your answer in standard form. Example 3 Continued To find the average spending per student, divide the total debt by the number of students. Simplify each quotient. Simplify the exponent. Write in standard form. The average spending per student is $5,800.

16. In 1990, the United States public debt was about dollars. The population of the United States was about people. What was the average debt per person? Write your answer in standard form. Check It Out! Example 3 To find the average debt per person, divide the total debt by the number of people. Write as a product of quotients.

17. In 1990, the United States public debt was about dollars. The population of the United States was about people. What was the average debt per person? Write your answer in standard form. Check It Out! Example 3 Continued To find the average debt per person, divide the total debt by the number of people. Simplify each quotient. Simplify the exponent. Write in standard form. The average debt per person was $12,800.

18. A power of a quotient can be found by first writing the numerator and denominator as powers. Notice that the exponents in the final answer are the same as the exponent in the original expression.

20. Example 4A: Finding Positive Powers of Quotient Simplify. Use the Power of a Quotient Property. Simplify.

21. Use the Power of a Product Property: Simplify and use the Power of a Power Property: Example 4B: Finding Positive Powers of Quotient Simplify. Use the Power of a Product Property.

22. Use the Power of a Product Property: Use the Power of a Product Property: Example 4C: Finding Positive Powers of Quotient Simplify. Use the Power of a Product Property.

23. Use the Power of a Product Property: Example 4C Continued Simplify.

24. Check It Out! Example 4a Simplify. Use the Power of a Quotient Property. Simplify.

25. Check It Out! Example 4b Simplify.

26. Check It Out! Example 4c Simplify.

27. . Remember that What if x is a fraction? Therefore, Write the fraction as division. Use the Power of a Quotient Property. Multiply by the reciprocal. Simplify. Use the Power of a Quotient Property.

29. and Example 5A: Finding Negative Powers of Quotients Simplify. Rewrite with a positive exponent. Use the Powers of a Quotient Property .

30. Example 5B: Finding Negative Powers of Quotients Simplify.

31. Example 5C: Finding Negative Powers of Quotients Simplify. Rewrite each fraction with a positive exponent. Use the Power of a Quotient Property. Use the Power of a Product Property: (3)2 (2n)3 = 32  23n3 and (2)2  (6m)3 = 22  63m3

32. 1 2 1 1 24 12 Example 5C: Finding Negative Powers of Quotients Simplify. Square and cube terms. Divide out common factors. Simplify.

33. Helpful Hint Whenever all of the factors in the numerator or the denominator divide out, replace them with 1.

34. Check It Out! Example 5a Simplify. Rewrite with a positive exponent. Use the power of a Quotient Property. 93=729 and 43= 64.

35. Check It Out! Example 5b Simplify. Rewrite with a positive exponent. Use the Power of a Quotient Property. Use the Power of a Power Property: (b2c3)4= b2•4c3•4 = b8c12 and (2a)4= 24a4= 16a4.

36. Add exponents and divide out common terms. Check It Out! Example 5c Simplify. Rewrite each fraction with a positive exponent. Use the Power of a Quotient Property. Use the Power of a Product Property: (3)2= 9.

37. 1. 3.4. 5. Lesson Quiz: Part I Simplify. 2.

38. Lesson Quiz: Part II Simplify. 6. Simplify (3  1012) ÷ (5  105) and write the answer in scientific notation. 6  106 7. The Republic of Botswana has an area of 6  105square kilometers. Its population is about 1.62  106. What is the population density of Botswana? Write your answer in standard form. 2.7 people/km2