8th grade · Math · Unit 12 of 17
Exponent Rules
Add, subtract, multiply exponents
What your child practices
Properties of integer exponents: multiplying and dividing powers with the same base, a power of a power, zero exponents and negative exponents.
Maine Learning Results learning standard: 8.EE.A.1 · applying the properties of integer exponents to write equivalent expressions
How we explain it
Children can open this short lesson before they practice.
- Multiply powers with the same base: add the exponents.
- Divide: subtract the exponents. Power of a power: multiply them.
- a⁰ = 1, and a⁻ⁿ = 1/aⁿ.
Example: Simplify 2³ × 2⁴. Same base, so add: 3 + 4 = 7. Answer: 2⁷
Exponent Rules in Maine
In the Maine Learning Results, this is unit 12 of 17 in 8th grade Math, after Congruent Shapes and before Systems of Equations.
Gradelings describes a child's practice on this unit as Beginning, Approaching, Meeting or Exceeding (Four practice steps). That reflects practice, not a report-card mark: the teacher decides the mark.
Source: Maine Department of Education
Sample questions
A taste of this unit. In the app, questions change every time and get easier or harder to match your child.
Question 1
Simplify 4³ ÷ 4².
- 4⁵
- 1¹
- 4²
- 4¹
4¹
Hint: When you divide powers with the same base, subtract the exponents.
Question 2
Simplify (6⁴)².
- 6⁶
- 6⁹
- 12⁴
- 6⁸
6⁸
Hint: A power of a power: multiply the exponents.
Question 3
What is 4⁻³?
- −64
- 64
- −1/64
- 1/64
1/64
Hint: A negative exponent means one over: 4⁻³ = 1/4³ = 1/64.
Question 4
What is the value of 3⁴ × 3⁻²?
- 9
- 81
- 729
- 27
9
Hint: Add the exponents: 4 + (-2) = 2. 3² = 9.
Question 5
Simplify 6³ × 6⁷.
- 6²¹
- 6⁴
- 6¹⁰
- 36¹⁰
6¹⁰
Hint: When you multiply powers with the same base, add the exponents.
Question 6
Simplify 9⁷ ÷ 9⁵.
- 9²
- 9¹
- 1²
- 9¹²
9²
Hint: When you divide powers with the same base, subtract the exponents.