Question

Tìm x biết

a, |x—3|=5

b, (x+2)²=81

Answer 1

a: =>x-3=5 hoặc x-3=-5

=>x=8 hoặc x=-2

b: =>x+2=9 hoặc x+2=-9

=>x=7 hoặc x=-11

Answer 2

Answer 3

`|x - 3| =  5`

\(\Rightarrow\left[{}\begin{matrix}x-3=5\\x-3=-5\end{matrix}\right.=>\left[{}\begin{matrix}x=8\\x=-2\end{matrix}\right.\)

Vậy.....

 

`(x+2)^2 = 81`

`(x+2)^2 = 9^2`

\(\Rightarrow\left[{}\begin{matrix}x+2=9\\x+2=-9\end{matrix}\right.=>\left[{}\begin{matrix}x=7\\x=-11\end{matrix}\right.\)

Vậy....

_____________________________________

`#BaoL i n h`