Bài 1:Tìm số nguyên x,biết a)|2x-16|=0 b)6.|x|-5=7 c)3.|2x-3|-16=-4 đ)26-|3x+2|=-13 23/11/2021 Bởi Mary Bài 1:Tìm số nguyên x,biết a)|2x-16|=0 b)6.|x|-5=7 c)3.|2x-3|-16=-4 đ)26-|3x+2|=-13
`a) |2x-16|=0` `<=> 2x-16=0` `<=> 2x=16` `<=> x=8` `b) 6|x|-5=7` `<=> 6|x|=7+5` `<=> 6|x|=12` `<=> |x|=2` `<=>`\(\left[ \begin{array}{l}x=2\\x=-2\end{array} \right.\) `c) 3|2x-3|-16=-4` `<=> 3|2x-3|=-4+16` `<=> 3|2x-3|=12` `<=> |2x-3|=4` `<=>`\(\left[ \begin{array}{l}2x-3=4\\2x-3=-4\end{array} \right.\) `<=>`\(\left[ \begin{array}{l}2x=7\\2x=-1\end{array} \right.\) `<=>`\(\left[ \begin{array}{l}x=\dfrac{7}{2}\\x=\dfrac{-1}{2}\end{array} \right.\) `d) 26-|3x+2|=-13` `<=> |3x+2|=26+13` `<=> |3x+2|=39` `<=>`\(\left[ \begin{array}{l}3x+2=39\\3x+2=-39\end{array} \right.\) `<=>`\(\left[ \begin{array}{l}3x=37\\3x=-41\end{array} \right.\) `<=>`\(\left[ \begin{array}{l}x=\dfrac{37}{3}\\x=\dfrac{-41}{3}\end{array} \right.\) Bình luận
Đáp án:
Giải thích các bước giải:
câu a
|2x-16|=0
2x-16=0
2x =16+0
2x =16
x =16÷2
x =8
`a) |2x-16|=0`
`<=> 2x-16=0`
`<=> 2x=16`
`<=> x=8`
`b) 6|x|-5=7`
`<=> 6|x|=7+5`
`<=> 6|x|=12`
`<=> |x|=2`
`<=>`\(\left[ \begin{array}{l}x=2\\x=-2\end{array} \right.\)
`c) 3|2x-3|-16=-4`
`<=> 3|2x-3|=-4+16`
`<=> 3|2x-3|=12`
`<=> |2x-3|=4`
`<=>`\(\left[ \begin{array}{l}2x-3=4\\2x-3=-4\end{array} \right.\)
`<=>`\(\left[ \begin{array}{l}2x=7\\2x=-1\end{array} \right.\)
`<=>`\(\left[ \begin{array}{l}x=\dfrac{7}{2}\\x=\dfrac{-1}{2}\end{array} \right.\)
`d) 26-|3x+2|=-13`
`<=> |3x+2|=26+13`
`<=> |3x+2|=39`
`<=>`\(\left[ \begin{array}{l}3x+2=39\\3x+2=-39\end{array} \right.\)
`<=>`\(\left[ \begin{array}{l}3x=37\\3x=-41\end{array} \right.\)
`<=>`\(\left[ \begin{array}{l}x=\dfrac{37}{3}\\x=\dfrac{-41}{3}\end{array} \right.\)