Question

| x-5|=|-7|

Answer 1

\(\left|x-5\right|=\left|-7\right|\)

\(\Rightarrow\left|x-5\right|=7\)

\(\Rightarrow x-5=7\) hoặc \(x-5=-7\)

+) \(x-5=7\Rightarrow x=12\)

+) \(x-5=-7\Rightarrow x=-2\)

Vậy \(x\in\left\{12;-2\right\}\)

Answer 2

\(\left|x-5\right|=\left|-7\right|=\left|7\right|=7\)

+) \(x-5=-7\) +) \(x-5=7\)

\(x=\left(-7\right)+5\) \(x=7+5\)

\(x=-2\) \(x=12\)

Vậy \(xE\left\{-2;12\right\}\)

Answer 3

/x-5/ = /-7/

=> /x-5/ = 7 => x = 12

/x-5/ = (-7) => x = (-2)

vậy x là : 12 ; (-2)