Verified answer

Объяснение:

як що тобі сподобалось то оціни мене

[tex]\displaystyle\bf\\1)\\\\4x^{2} +16x\geq 20\\\\4x^{2} +16x-20\geq 0\\\\x^{2} +4x-5\geq 0\\\\(x-1)(x+5)\geq 0\\\\\\+ + + + + \Big[-5\Big] - - - - - \Big[1\Big] + + + + + \\\\\\Otvet \ : \ x\in\Big(-\infty \ ; \ -5\Big]\cup\Big[1 \ ; \ +\infty \Big)\\\\2)\\\\x^{2} < 25\\\\x^{2} -25 < 0\\\\(x-5)\cdot(x+5) < 0\\\\\\+ + + + + \Big(-5\Big) - - - - - \Big(5\Big)+ + + + + \\\\\\Otvet \ : \ x\in\Big(-5 \ ; \ 5\Big)[/tex]

[tex]\displaystyle\bf\\3)\\\\x^{2} -6x+9\leq 0\\\\(x-3)^{2} \leq 0\\\\x-3=0\\\\x=3\\\\Otvet \ : \ 3[/tex]