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Powers and Exponents Lesson #2 Pg. 175 What You’ll Learn • Power – Numbers using an exponent and base • Base – The common factor in a power • Exponent – The number of times the base is used as a factor • https://www.youtube.com/watch?v=wCFSy_JKz3g Write and Evaluate Powers • A product of repeated factors can be expressed as a power, that is, using an exponent and a base. 44 factors 64444 7 444448 4 2 g2 g2 g2 2 The base is the common factor The exponent tells how many times the base is used as a factor Read and Write Powers Read and Write Powers Power 1 3 2 3 3 3 4 3 Words Factors 3 to the first power 3 3g3 3 to the second power or 3 squared 3 to the third power or 3 cubed 3 to the forth power or 3 to the forth M M n 3 to the nth power or 3 to the nth 3 3g3g3 3g3g3g3 M 3144442 g3g3g L g3 44443 n factors Negatives Raised to Exponents • (-) Raised to Even Exponents – Will be positive (+) • (-) Raised to Odd Exponents – Will be negative (-) • Watch for Parentheses (-3)2 -32 -(3)2 Examples • Write each expression using exponents #1. 2 g 2 g 2 # 2. a g b g b g a g b g3 g3 g3 g3 Evaluate Examples 2 3 4 2 5 1 5 3 • The deck of a skateboard has an area of about 25 • 7 in2. What is the area of the skateboard deck? Substitution Examples • Evaluate each expression if a = 3 and b = 5 a 2 b4 a b 2 Substitution • Evaluate if c = - 4 and d = 9 c d 3 2 d 3 c2 2 c d 3 HOMEWORK HC: pg. 179-180 (1-16) CC: pg. 179-180 (1-14, 16) www.ixl.com 8th D1