Question:
$\frac{5 x}{2}+\frac{3 x}{4} \geq \frac{39}{4}$
Solution:
$\frac{5 x}{2}+\frac{3 x}{4} \geq \frac{39}{4}$
$\Rightarrow \frac{10 x+3 x}{4} \geq \frac{39}{4}$
$\Rightarrow 10 x+3 x \geq 39$
$\Rightarrow 13 x \geq 39$
$\Rightarrow x \geq \frac{39}{13} \quad$ (Dividing both the sides by 13$)$
$\Rightarrow x \geq 3$
Hence, the solution set of the given inequation is $[3, \infty)$.