UGAT Bangalore: AlgebraInequalities. Free, no login required.

$1 \leq y + z \leq 8$

$0 < y + z \leq 8$

$0 < y + z < 9$

$-1.5 < y + z < 9$

$x \geq -\frac{1}{4}, or\, x \leq 2$

$x \geq -\frac{1}{5}, or\, x \leq 3$

$x \leq -\frac{1}{5}, or\, x \geq 3$

$x \leq -\frac{1}{4}, or\, x \geq 2$