Grade 8 · Algebra & functions

Exponent rules practice

Exponent rules is a grade 8 math skill aligned to Common Core standard 8.EE.A.1: know and apply the properties of integer exponents to generate equivalent numerical expressions. Below are 8 practice questions with answers and step-by-step explanations, drawn from the 220 exponent rules problems our math games drill.

CCSS 8.EE.A.1220 questions in the bank
Sample questions

Try 8 for free

Question 1easy

272426=2n\dfrac{2^{7} \cdot 2^{4}}{2^{6}} = 2^{n}. What is nn?

Add the exponents in the numerator, then subtract: 27+426=2116=25\dfrac{2^{7+4}}{2^{6}} = 2^{11-6} = 2^{5}, so n=5n = 5.

Question 2easy

Rewrite a2a^{-2} with a positive exponent.

Negative exponent: a2=1a2a^{-2} = \dfrac{1}{a^{2}}.

Question 3easy

(37)4=3a7a(3 \cdot 7)^{4} = 3^{a} \cdot 7^{a}. What is aa?

Power of a product: the exponent applies to each factor. (37)4=3474(3 \cdot 7)^{4} = 3^{4} \cdot 7^{4}, so a=4a = 4.

Question 4easy

Simplify: (y5)2(y^{5})^{2}.

Power rule: multiply exponents. y52=y10y^{5 \cdot 2} = y^{10}.

Question 5easy

Simplify: y6y3y^{6} \cdot y^{3}.

Product rule: add exponents. y6+3=y9y^{6+3} = y^{9}.

Question 6easy

Simplify: b8b4\dfrac{b^{8}}{b^{4}}.

Quotient rule: subtract exponents. b84=b4b^{8-4} = b^{4}.

Question 7easy

Simplify: y0y^0 (where y0y \neq 0).

Any nonzero base to the zero power equals 1.

Question 8easy

(34)235=3k\dfrac{(3^{4})^{2}}{3^{5}} = 3^{k}. What is kk?

Power of a power first: (34)2=38(3^{4})^{2} = 3^{8}; then the quotient rule gives 385=333^{8-5} = 3^{3}, so k=3k = 3.

Play it

Math games for Grade 8

Questions like these are served inside our head-to-head math games.

Drill it inside a game.

The free placement test finds your level, then every match serves exponent rules questions at exactly the right difficulty.