advertisement

Math 8 Chapter 1 Lesson 2 page 15 Page 15 Essential Question: Why is it helpful to write numbers in different ways? Common Core State Standards: 8.EE.1 Mathematical Practices: 1,3,4, 8 I can use powers and exponents to write large and small numbers Calculators Engage Vocabulary Notes Vocabulary Word Power A product of repeated factors expressed using an exponent and a base. Base In a power, the number that is the common factor. Exponent In a power, the number of times the base is used as a factor. Symbols Model Notes Power Base Exponent Or Calculator Value Explore/Explain Chart Internet Activity Powers Examples - Complete Problem (-2)(-2)(-2)*3*3*3*3 a*b*b*a*b (-2/3)4 25*7 a2 + b4 If a=3 and b=5 (a - b)2 If a=3 and b=5 x3 + y5 If x=4 and y=2 Base Exponent Power Value Elaborate Guided Practice Guided Practice page 18 ODD Problems and Answers Write using exponents. 1. (-11)(-11)(-11) = (-11)3 Write using exponents. 3. r*s*r*r*s*s*r*r = r5*s3 Evaluate. 5. (-4)4 = -4*-4*-4*-4 = 16*16 = 256 Animal Weight (lb) Value Black Bear 2*52*7 2*25*7 = 50*7= 350 lbs Key Deer 3*52 3*25 = 75 lbs Panther 23*3*5 8*3*5 = 24*5 = 120 lbs 7. The table shows the average weights of some endangered mammals. What is the weight of each animal? Evaluate each expression if x=2 and y=10. (x2 +y)3 = (22 +10)3 = (2*2 +10)3 = (4 +10)3 = (14)3 =14*14*14 2,744 Guided Practice page 18 EVEN Answers Guided Practice Page 18 - Even 2. 23*33 4. 64 6. 1/343 8. 10,004 10. The repeated factor is the base. The number of times it repeats is the exponent. Explore/Explain Got It Problems Got it A-C page 16 Write using exponents A. ½ * ½ * ½ * ½ B. 4*4*4*5*5 C. m*m*n*n*m Got it A-C Answers page 16 Write using exponents A. ½ * ½ * ½ * ½ = (1/2)4 B. 4*4*4*5*5 = 43*52 C. m*m*n*n*m = m3*n2 Got it D-F page 17 Evaluate D. 44 E. (-2) 6 F. (1/5) 3 Got it D-F Answers page 17 Evaluate D. 44 = 256 E. (-2) 6 = 64 F. (1/5) 3 = 1/125 Got it G page 17 G. A school basketball court has an area of 23*3*52*7 square feet. What is the area of a school basketball court? Got it G Answer page 17 G. A school basketball court has an area of 23*3*52*7 square feet. What is the area of a school basketball court? 2*2*2*3*5*5*7 = 8*3*25*7 = 200 * 21 = 4,200 sq ft Got it H-J page 18 Evaluate each expression if c=-4 and d=9. H. c3 + d3 I. (c+d) 3 J. d3 – (c3 – 2) Got it H-J Answers page 18 Evaluate each expression if c=-4 and d=9. H. (-4)3 + 92 = -4*-4*-4 + 9*9 = -64+81 = 17 I. ((-4)+9) 3 = 53 = 5*5*5 = 125 J. 93 – ((-4)2 – 2) = 93 – (-4*-4 – 2) = 93 – (16 – 2) = 93 – (14) = 9*9*9 - 14 = 729 – 14 = 715 Evaluate Classwork Activities Classwork 1. Find Someone Who Grade/Collect 2. Extra Practice pgs 21-22 HDIF (20 problems – 20 minutes) Exchange and grade 3. Worksheets PreAlgw/pizzaz 62: Algw/pizzaz 8 4. Foldable – File in Folder Homework Independent Practice pages 19-20