Question: Solve $x+5>4 x-10$, when $x \in R$
Solution:
$x+5>4 x-10$
$\Rightarrow 5+10>4 x-x$
$\Rightarrow 15>3 x$
Divide by 3
$\Rightarrow 5>x$
$\Rightarrow x<5$
$x<5$ means $x$ is from $-\infty$ to 5 that is $x \in(-\infty, 5)$
Hence solution of $x+5>4 x-10$ is $x \in(-\infty, 5)$