Question

Find the value of m
$5^{m+2}$ $\times$ $5^4$ = $5^3$.

• A. 0
• B. -4
• C. 1
• D. -3

Answer 1

The correct option is D

-3

$a^m$ $\times$ $a^n$ = $a^{m+n}$
So
$5^{m+2}$ $\times$ $5^4$ = $5^{m+2+4}$ = $5^{m+6}$
$5^{m+6}$ = $5^3$
Equating the exponents,
$\Rightarrow$$m+6=3$
$\Rightarrow$$m=3-6$
$\Rightarrow$$m=-3$