If the expression 7^(15) was simplified using the Power Rule of Exponents, which of the following would be an expanded equivalent expression? (1 point)

(7· 7· 7· 7· 7)^10
(7^(10))^5
(7· 7· 7)· (7· 7· 7)· (7· 7· 7)· (7· 7· 7)· (7· 7· 7)
(7^18))^3

1 answer

To find an expanded equivalent expression for \( 7^{15} \) using the Power Rule of Exponents, we will evaluate each of the provided options to see if they equate to \( 7^{15} \).

  1. Option: \( (7 \cdot 7 \cdot 7 \cdot 7 \cdot 7)^{10} \)

    • This can be rewritten as \( 7^5 \) raised to the power of 10, which equals \( 7^{5 \cdot 10} = 7^{50} \).
    • This is NOT equal to \( 7^{15} \).
  2. Option: \( (7^{10})^5 \)

    • Using the Power Rule: \( (a^m)^n = a^{m \cdot n} \), this becomes \( 7^{10 \cdot 5} = 7^{50} \).
    • This is NOT equal to \( 7^{15} \).
  3. Option: \( (7 \cdot 7 \cdot 7) \cdot (7 \cdot 7 \cdot 7) \cdot (7 \cdot 7 \cdot 7) \cdot (7 \cdot 7 \cdot 7) \cdot (7 \cdot 7 \cdot 7) \)

    • There are 5 groups of \( (7 \cdot 7 \cdot 7) \), each contributing \( 7^3 \). Thus, this expression equals \( (7^3)^5 \).
    • Applying the Power Rule: \( 7^{3 \cdot 5} = 7^{15} \).
    • This is equal to \( 7^{15} \).
  4. Option: \( (7^{18})^3 \)

    • Using the Power Rule: this becomes \( 7^{18 \cdot 3} = 7^{54} \).
    • This is NOT equal to \( 7^{15} \).

Thus, the only expression that simplifies to \( 7^{15} \) is: (7· 7· 7)· (7· 7· 7)· (7· 7· 7)· (7· 7· 7)· (7· 7· 7).