Question:
Solve each of the following system of equations in R.
6. 2x − 3 < 7, 2x > −4
Solution:
$2 x-3<7$
$\Rightarrow 2 x<7+3$
$\Rightarrow x<5$
$\Rightarrow x \in(-\infty, 5) \quad \ldots(\mathrm{i})$
Also, $2 x>-4$
$\Rightarrow x>-2$
$\Rightarrow x \in(-2, \infty) \quad \ldots$ (ii)
Thus, the solution of the given set of inequalities is the intersection of (i) and (ii).
$(-\infty, 5) \cap(-2, \infty)=(-2,5)$
Thus, the solution of the given set of inequalities is $(-2,5)$.