Lưu avatar Toán Học Tìm x , biết A) | x-3 | - 16 = -4 B) 26 - | x + 9 | = -13 c) | x - 1 | + 15 = 18

Lời giải chi tiết:

`a)` `|x-3|-16=-4`

`=>|x-3|=-4+16`

`=>|x-3|=12`

`=>`\(\left[ \begin{array}{l}x-3=12\\x-3=-12\end{array} \right.\)

`=>`\(\left[ \begin{array}{l}x=12+3\\x=-12+3\end{array} \right.\)

`=>`\(\left[ \begin{array}{l}x=15\\x=-9\end{array} \right.\)

Vậy `x=15` hoặc `x=-9`

`b)` `26-|x+9|=-13`

`=>|x+9|=26-(-13)`

`=>|x+9|=39`

`=>`\(\left[ \begin{array}{l}x+9=39\\x+9=-39\end{array} \right.\)

`=>`\(\left[ \begin{array}{l}x=39-9\\x=-39-9\end{array} \right.\)

`=>`\(\left[ \begin{array}{l}x=30\\x=-48\end{array} \right.\)

Vậy `x=30` hoặc `x=-48`

`c)` `|x-1|+15=18`

`=>|x-1|=18-15`

`=>|x-1|=3`

`=>`\(\left[ \begin{array}{l}x-1=3\\x-1=-3\end{array} \right.\)

`=>`\(\left[ \begin{array}{l}x=3+1\\x=-3+1\end{array} \right.\)

`=>`\(\left[ \begin{array}{l}x=4\\x=-2\end{array} \right.\)

Vậy `x=4` hoặc `x=-2`

`@uniquetimehunter`