\(\left(\frac{3x}{7}+1\right):\left(-4\right)=\frac{-1}{28}\)
\(\Leftrightarrow\frac{3x+7}{7}.\frac{1}{-4}=\frac{-1}{28}\)
\(\Leftrightarrow-\frac{3x+7}{28}=\frac{-1}{28}\)
\(\Leftrightarrow-\left(3x+7\right)=-1\)
\(\Leftrightarrow3x+7=1\)\(\Leftrightarrow3x=-6\)
\(\Leftrightarrow x=-2\)
Bài 1 : Tính
1) \(\frac{4}{7}-\frac{1}{14}+\left|\frac{-5}{21}\right|\)
2) \(\left|\frac{-2}{3}\right|-\frac{1}{2}+3\)
3) \(\left|\frac{7}{-4}\right|-\frac{5}{8}+\frac{-2}{3}\)
4) \(\frac{4}{5}+\left|\frac{-3}{2}\right|+\frac{1}{-4}\)
5) \(\left|\frac{-1}{4}\right|-3+\frac{3}{4}\)
6) \(\left|\frac{-1}{3}\right|-\frac{5}{4}+\frac{1}{5}\)
Bài 2 : Tìm x, biết :
1) \(x-\left|1\frac{1}{6}\right|=\frac{5}{21}\)
2) \(x+\left|-1\frac{2}{3}\right|=\left|-\frac{3}{4}\right|\)
3) \(\left|x-\frac{1}{3}\right|=\frac{5}{2}\)
4) \(\left|x+\frac{2}{3}\right|=0\)
5) \(\left|x+2\right|=\frac{1}{3}-\frac{1}{5}\)
6) \(\left|x-4\right|=\frac{1}{5}-\left(\frac{1}{2}-\frac{5}{4}\right)\)
7) \(\left|x-\frac{5}{4}\right|=-\frac{1}{3}\)
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E cần gấp lắm ạ, cảm ơn.
Bài 1 : Tính
1) \(\frac{4}{7}-\frac{1}{14}+\left|\frac{-5}{21}\right|\)
2) \(\left|\frac{-2}{3}\right|-\frac{1}{2}+3\)
3) \(\left|\frac{7}{-4}\right|-\frac{5}{8}+\frac{-2}{3}\)
4) \(\frac{4}{5}+\left|\frac{-3}{2}\right|+\frac{1}{-4}\)
5) \(\left|\frac{-1}{4}\right|-3+\frac{3}{4}\)
6) \(\left|\frac{-1}{3}\right|-\frac{5}{4}+\frac{1}{5}\)
Bài 2 : Tìm x, biết :
1) \(x-\left|1\frac{1}{6}\right|=\frac{5}{21}\)
2) \(x+\left|-1\frac{2}{3}\right|=\left|-\frac{3}{4}\right|\)
3) \(\left|x-\frac{1}{3}\right|=\frac{5}{2}\)
4) \(\left|x+\frac{2}{3}\right|=0\)
5) \(\left|x+2\right|=\frac{1}{3}-\frac{1}{5}\)
6) \(\left|x-4\right|=\frac{1}{5}-\left(\frac{1}{2}-\frac{5}{4}\right)\)
7) \(\left|x-\frac{5}{4}\right|=-\frac{1}{3}\)
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E đang cần gấp, cảm ơn :)
Bài 1 Tìm x ,y biết
a, 2| 2x -3 | =1
b,7,5 -3 | 5 -2x | = -4,5
c, | 3x-4 | + | 3y +5 |=0
Bài 2 Tìm x biết
a, \(\left|\frac{5}{3}x\right|\) =\(\left|-\frac{1}{6}\right|\)
b, \(\left|\frac{3}{4}x-\frac{3}{4}\right|-\frac{3}{4}=\left|-\frac{3}{4}\right|\)
c, \(\left|x+\frac{3}{5}\right|-\left|x-\frac{7}{3}\right|=0\)
Bài 3 Tìm x biết
a,| x |+| x+2 |=0
b,\(\left|x\left(x^2-\frac{5}{4}\right)\right|=x\)
\(a,1\frac{13}{15}.0,75-\left(\frac{8}{15}+0,25\right).\frac{24}{47}\)
\(b,5:\left(4\frac{3}{4}-1\frac{25}{28}\right)-1\frac{3}{8}:\left(\frac{3}{8}+\frac{9}{20}\right)\)
\(c,6\frac{5}{12}:2\frac{3}{4}+11\frac{1}{4}.\left(\frac{1}{3}-\frac{1}{5}\right)\)
\(d,\left(\frac{3}{5}+0,415-\frac{3}{200}\right).2\frac{2}{3}.0,25\)
\(e,\left(\frac{3}{8}+\frac{-3}{4}+\frac{7}{12}\right):\frac{5}{6}+\frac{1}{2}\)
\(g,1\frac{13}{15}.0,75-\left(\frac{11}{20}+25\%\right);\frac{7}{3}\)
\(-3xy+4y-6x=27\\ \Rightarrow-y\left(3x-4\right)-6x+8=35\\ \Rightarrow-y.\left(3x-4\right)-2\left(3x-4\right)=35\\ \Rightarrow\left(3x-4\right)\left(-y-2\right)=35\)
\(\Rightarrow3x-4=-1;-y-2=-35\)
hoặc \(3x-4=-5;-y-2=-7\)
hoặc \(3x-4=-7;-y-2=-5\)
hoặc \(3x-4=-35;-y-2=-1\)
hoặc \(3x-4=1;-y-2=35\)
hoặc \(3x-4=5;-y-2=7\)
hoặc \(3x-4=7;-y-2=5\)
hoặc \(3x-4=35;-y-2=1\)
\(\Rightarrow x=1;y=33\)
hoặc \(x=-\frac{1}{3};y=5\) ( loại vì x,y thuộc Z )
hoặc \(x=-1;y=3\)
hoặc \(x=-\frac{31}{3};y=-1\) ( loại vì x,y thuộc Z )
hoặc \(x=\frac{5}{3};y=-37\) ( loại vì x,y thuộc Z )
hoặc \(x=3;y=-9\)
hoặc \(x=\frac{10}{3};y=-7\) (loại vì x,y thuộc Z )
hoặc \(x=\frac{39}{3};y=-3\) ( loại vì x,y thuộc Z )
vậy \(\left(x,y\right)\in\left\{\left(1;33\right);\left(-1;3\right);\left(3;-9\right)\right\}\)
Bài 2 : Tìm x, biết :
1) \(x-\left|1\frac{1}{6}\right|=\frac{5}{21}\)
2) \(x+\left|-1\frac{2}{3}\right|=\left|-\frac{3}{4}\right|\)
3) \(\left|x-\frac{1}{3}\right|=\frac{5}{2}\)
4) \(\left|x+\frac{2}{3}\right|=0\)
5) \(\left|x+2\right|=\frac{1}{3}-\frac{1}{5}\)
6) \(\left|x-4\right|=\frac{1}{5}-\left(\frac{1}{2}-\frac{5}{4}\right)\)
7) \(\left|x-\frac{5}{4}\right|=-\frac{1}{3}\)
Bài 1:
1. Tính: \(E=1+\frac{1}{2}\left(1+2\right)+\frac{1}{3}\left(1+2+3\right)+\frac{1}{4}\left(1+2+3+4\right)+...+\frac{1}{200}\left(1+2+...+200\right)\)
2. Tìm và tính tổng các số nguyên x thỏa mãn: \(\frac{21}{5}\left|x\right|< 2019\)
3. Tìm x, biết: \(\frac{2^{24}\left(x-3\right)}{\left(3\frac{5}{7}-1,4\right)\left(6\cdot2^{24}-4^{13}\right)}=\left(\frac{5}{3}\right)^2\)
Bài 1: Tìm x a) \(\frac{1}{7}\cdot\left|x\right|-\frac{4}{5}=\frac{1}{5}\) b) \(\left(\frac{3}{4}-x\right)^3=-27\) c) \(\frac{x-1}{-2}=\frac{-8}{x-1}\) d) \(\left|2x-3\right|+4\cdot\left(-5\right)^2=101\)
Bài 1, Tìm x biết
a, \(\left|\frac{5}{3}x\right|=-\frac{1}{6}\)
b, \(\left|\frac{3}{4}x-\frac{3}{4}\right|-\frac{3}{4}=-\frac{3}{4}\)
c, \(\left|x+\frac{3}{5}\right|-\left|x-\frac{7}{3}\right|=0\)
