Simplify the Expression: 8³ × 8 Using Exponent Rules

To simplify the expression $8^3 \times 8$, we begin by identifying the implicit exponent for the standalone 8. Since there is no written exponent next to the second 8, we can assume it has an exponent of 1.

Thus, the expression can be written as:\br $8^3 \times 8^1$.

Using the rule for multiplying powers with the same base, $a^m \times a^n = a^{m+n}$, we add the exponents:

• Here, the base $a$ is 8.
• The exponents are 3 and 1.

Therefore, $8^3 \times 8^1 = 8^{3+1} = 8^4$.

Thus, the simplified expression is $\mathbf{8^4}$.

Consequently, the correct choice is $8^{3+1}$.