`a)x²=16`
`⇔x=±4`
`b)x²=17`
`⇔x=±\sqrt{17}`
`c)(x-5)²=4/9`
`⇔x-5=2/3`
`⇔x=(17)/3`
`d)x²-6x+8=0`
`⇔x²-2x-4x+8=0`
`⇔x(x-2)-4(x-2)=0`
`⇔(x-2)(x-4)=0`
`⇔x=2` hoặc `x=4`
`e)\sqrt{x+3}=5`
`⇔x+3=25`
`⇔x=22`
`f)\sqrt{x²}=17-\sqrt{16}`
`⇔x²=13²`
`⇔x²=169`
`⇔x=±13`
`g)\sqrt{(x-5)²}=4/9`
`⇔x-5=4/9` hoặc `x-5=-4/9`
`⇔x=(49)/9` hoặc `x=(41)/9`