Answer
$(-\infty, +\infty)$
Work Step by Step
Simplify the right side to obtain:
$f(x) = 2(x) + 2(5)
\\f(x) =2x+10$
This function is defined for all real number values of $x$, therefore its domain is the set of all real numbers.
Thus, the domain is $(-\infty, +\infty)$.
