Answer
$x=1$
Work Step by Step
Recall the rule that
$a^m=a^n \longrightarrow m=n$ if $a\ne1,a\ne-1$
Applying this rule, we obtain:
$(2^{x}) (5)=10^x \\ (2^x)(5) =(2 \cdot 5)^{x} \\ (2^x)(5)=2^{x} \cdot 5^x \\5^1 =5^x$
The base is the same, so their exponents can be equal.
Therefore, we have: $x=1$