Question:
Solve each of the following system of equations in R.
2. 2x − 7 > 5 − x, 11 − 5x ≤ 1
Solution:
We have, $2 x-7>5-x$
$\Rightarrow 2 x+x>5+7$
$\Rightarrow 3 x>12$
$\Rightarrow x>4$
$\Rightarrow x \in(4, \infty) \ldots$ (i)
Also, $11-5 x \leq 1$
$\Rightarrow 5 x \geqslant 11-1$
$\Rightarrow x \geqslant 2$
$\Rightarrow x \in[2, \infty) \ldots$ (ii)
$S$ olution set of the given set of inequations is intersection of (i) and (ii)
$(4, \infty) \cap[2, \infty)=(4, \infty)$
Thus, the solution set of the given set of inequations is $(4, \infty)$.