Question

народ помогите пожалуйста дз не успеваю сделать через 10 мин здать надо

Answer 1

$\displaystyle\bf\\1)\\\\\left \{ {{\dfrac{x}{3} +\dfrac{x}{4} } <7\atop {x(x-2)-(x+3)^{2} }<-9} \right. \\\\\\\left \{ {{\dfrac{x}{3} \cdot12+\dfrac{x}{4} } \cdot12<7\cdot12\atop {x^{2} -2x-x^{2} -6x-9<-9} \right. \\\\\\\left \{ {{4x+3x<84} \atop {-8x<0}} \right. \\\\\\\left \{ {{7x<84} \atop {x>0}} \right. \\\\\\\left \{ {{x<12} \atop {x>0}} \right. \\\\\\Otvet:x\in(0 \ ; \ 12)$

$\displaystyle\bf\\2)\\\\\left \{ {{\dfrac{x}{2} \leq 0} \atop {2-x>0}} \atop{2-x\geq 2x+1} \right. \\\\\\\left \{ {{x\leq 0} \atop {-x>-2}} \atop{-3x\geq -1} \right. \\\\\\\left \{ {{x\leq 0} \atop {x<2}} \atop{x\leq \dfrac{1}{3} } \right. \ \ \Rightarrow \ x\leq 0\\\\\\Otvet:x\in\Big(-\infty \ ; \ 0\Big]$