a.\(\Rightarrow\)\(\left\{{}\begin{matrix}x-2=3\\x-2=-3\end{matrix}\right.\)
\(\Rightarrow\left\{{}\begin{matrix}x=5\\x=-1\end{matrix}\right.\)
b.\(\Rightarrow\)\(\left\{{}\begin{matrix}x-3=20\\x-3=-20\end{matrix}\right.\)
\(\Rightarrow\)\(\left\{{}\begin{matrix}x=23\\x=-17\end{matrix}\right.\)
c.
a) \(\left|x-2\right|=3\)
\(\circledast\) TH1: x-2=3
x=3+2
x=5
\(\circledast\) TH2: x-2=-3
x=-3+2
x=-1
Vậy x\(\in\){-1;5}.
b) \(\left|x-3\right|-7=13\)
\(\left|x-3\right|=13+7\)
\(\left|x-3\right|=20\)
\(\circledast\) TH1: x-3=20
x=20+3
x=23
\(\circledast\) TH2: x-3=-20
x=-20+3
x=-17
Vậy x\(\in\){-17;23}.
c) \(72-3\cdot\left|x+1\right|=9\)
\(3\cdot\left|x+1\right|=72-9\)
\(3\cdot\left|x+1\right|=63\)
\(\left|x+1\right|=\dfrac{63}{3}\)
\(\left|x+1\right|=21\)
\(\circledast\) TH1: x+1=21
x=21-1
x=20
\(\circledast\) TH2: x+1=-21
x=-21-1
x=-22
Vậy x\(\in\){-22;20}.
d) \(17-\left(43-\left|x\right|\right)=45\)
\(43-\left|x\right|=17-45\)
\(43-\left|x\right|=-28\)
\(\left|x\right|=43-\left(-28\right)\)
\(\left|x\right|=71\)
x=71 hoặc x=-71
Vậy x\(\in\){-71;71}.
e) \(3\left|x-1\right|-5=7\)
\(3\left|x-1\right|=7+5\)
\(3\left|x-1\right|=12\)
\(\left|x-1\right|=\dfrac{12}{3}\)
\(\left|x-1\right|=4\)
\(\circledast\) TH1: x-1=4
x=4+1
x=5
\(\circledast\) TH2: x-1=-4
x=-4+1
x=-3
Vậy x\(\in\){-3;5}.
