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Laws of Exponents | Grade 8

Student Concept Worksheet Answers
#AnswerExplanation
1x^7Product rule: 5+2=7
2y^5Quotient rule: 9-4=5
3a^15Power rule: 3 times 5=15
41/93^(-2) = 1/3^2 = 1/9
51Zero exponent rule
62^10 = 1024(2^3)^2 = 2^6, then 2^6 times 2^4 = 2^10
Practice Worksheet Answers

Part A: Product Rule

#Answer
1x^7
2y^9
3a^6
42^7 = 128
5m^12
6b^9

Part B: Quotient Rule

#Answer
7x^5
8y^7
9a^0 = 1
105^4 = 625
11m^8
12z^5

Part C: Power Rule

#Answer
13x^10
14y^12
15a^12
162^12 = 4096
17m^20
18b^10

Part D: Zero/Negative Exponents

#Answer#Answer
191201
211/16221/25
231/x^3241/10 = 0.1

Part E: Mixed

#AnswerWork
25x^10(x^3)^2=x^6, x^6 times x^4=x^10
26y^2(y^2)^3=y^6, y^8/y^6=y^2
27a^18a^4 times a^2=a^6, (a^6)^3=a^18
282^2 = 4(2^3)^2=2^6, 2^6/2^4=2^2

Part F: Scientific Notation

#Answer
2935,000
300.0021
314.5 times 10^4
326.7 times 10^(-3)

Challenge

33
x^2 times y^3
(x^4 times y^3)^2 = x^8 times y^6. (x^2 times y)^3 = x^6 times y^3. Divide: x^(8-6) times y^(6-3) = x^2 times y^3
34
x = 5
2^5 = 32
FAST Practice Quiz Answers
1
B) x^8
Product rule: 5+3=8
2
B) y^6
Quotient rule: 10-4=6
3
B) a^12
Power rule: 4 times 3=12
4
Select: 5^0, x^0, (-7)^0
5^0 = 1 ✓
2^(-2) = 1/4 ✗
x^0 = 1 ✓
(-7)^0 = 1 ✓
5
C) 1/9
3^(-2) = 1/3^2 = 1/9
6
B) 2^8
(2^3)^2 = 2^6, then 2^6 times 2^2 = 2^8
Scoring Guide
ScoreInterpretationAction
6/6MasteryReady for scientific notation and polynomial operations
4-5/6ApproachingReview confused rules (product vs power, negative exponents)
2-3/6DevelopingReteach with expanded form. Show why rules work.
0-1/6InterventionStart with meaning of exponents. Build from 2^3 = 2 times 2 times 2