# How do you find the domain for g(x)=sqrt(40-8x)?

$g \left(x\right) = \sqrt{40 - 8 x}$
$g \left(x\right)$ is defined for all Real values of $x$ for which $\left(40 - 8 x\right) \ge 0$
That is for all Real values of $x \le 5$
So the Domain of $g \left(x\right)$ is $\left(- \infty , + 5\right]$