a, 5- \(\dfrac{2}{3}X\) =2
\(\dfrac{2}{3}x=5-\left(-2\right)\)
\(\dfrac{2}{3}x=7\)
x=\(7:\dfrac{2}{3}\)
x=10,5
vậy x=10,5
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ĐỀ 1:
1. Tính:
a. dfrac{7}{23}left[left(dfrac{-8}{6}right)-dfrac{45}{18}right]
b. dfrac{1}{5}:dfrac{1}{10}-dfrac{1}{3}left(dfrac{6}{5}-dfrac{9}{4}right)
c. dfrac{3}{5}.left(dfrac{-8}{3}right)-dfrac{3}{5}:left(-6right)
d. dfrac{1}{2}left(dfrac{4}{3}+dfrac{2}{5}right)-dfrac{3}{4}left(dfrac{8}{9}+dfrac{16}{3}right)
e. dfrac{6}{7}:left(dfrac{3}{26}-dfrac{3}{13}right)+dfrac{6}{7}left(dfrac{1}{10}-dfrac{8}{5}right)
2. Tìm x, biết:
a. 1dfrac{2}{5}x+dfrac{3}{7}dfrac{4}{5}
b. |x - 1,5| 2
c. df...
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ĐỀ 1:
1. Tính:
a. \(\dfrac{7}{23}\left[\left(\dfrac{-8}{6}\right)-\dfrac{45}{18}\right]\)
b. \(\dfrac{1}{5}:\dfrac{1}{10}-\dfrac{1}{3}\left(\dfrac{6}{5}-\dfrac{9}{4}\right)\)
c. \(\dfrac{3}{5}.\left(\dfrac{-8}{3}\right)-\dfrac{3}{5}:\left(-6\right)\)
d. \(\dfrac{1}{2}\left(\dfrac{4}{3}+\dfrac{2}{5}\right)-\dfrac{3}{4}\left(\dfrac{8}{9}+\dfrac{16}{3}\right)\)
e. \(\dfrac{6}{7}:\left(\dfrac{3}{26}-\dfrac{3}{13}\right)+\dfrac{6}{7}\left(\dfrac{1}{10}-\dfrac{8}{5}\right)\)
2. Tìm x, biết:
a. \(1\dfrac{2}{5}x+\dfrac{3}{7}=\dfrac{4}{5}\)
b. |x - 1,5| = 2
c. \(\dfrac{4}{5}-\left|x-\dfrac{1}{6}\right|=\dfrac{2}{3}\)
d. 3x . 2x = 216
e. \(\dfrac{1}{2}\left(x-\dfrac{1}{3}\right)+\dfrac{-1}{2}=\dfrac{3}{4}\)
* Lm nhanh nha
Ths you <3
ĐỀ 2:
1. Tính:
A. left(-dfrac{2}{3}right)^2+left(-dfrac{7}{8}right)+left(-dfrac{11}{12}right)
B. left(dfrac{-1}{3}right)^2:dfrac{1}{6}-2.left(dfrac{-1}{2}right)^3
C. dfrac{-1}{5}-left(dfrac{1}{2}+dfrac{3}{4}right)^2:dfrac{5}{8}
D. left|dfrac{-3}{2}+1,2right|+1dfrac{2}{3}:6
2. Tìm x, biết:
a. dfrac{2}{3}x-dfrac{1}{3}xdfrac{5}{12}
b. left(x-dfrac{12}{7}right):1dfrac{1}{5}dfrac{4}{7}
c. dfrac{2}{5}+left|x+1right|dfrac{3}{4}
3. Tìm x, y biết:
a. dfrac{x}{18}dfrac{y}{15}và x - y -30
b. 7...
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ĐỀ 2:
1. Tính:
A. \(\left(-\dfrac{2}{3}\right)^2+\left(-\dfrac{7}{8}\right)+\left(-\dfrac{11}{12}\right)\)
B. \(\left(\dfrac{-1}{3}\right)^2:\dfrac{1}{6}-2.\left(\dfrac{-1}{2}\right)^3\)\
C. \(\dfrac{-1}{5}-\left(\dfrac{1}{2}+\dfrac{3}{4}\right)^2:\dfrac{5}{8}\)
D. \(\left|\dfrac{-3}{2}+1,2\right|+1\dfrac{2}{3}:6\)
2. Tìm x, biết:
a. \(\dfrac{2}{3}x-\dfrac{1}{3}x=\dfrac{5}{12}\)
b. \(\left(x-\dfrac{12}{7}\right):1\dfrac{1}{5}=\dfrac{4}{7}\)
c. \(\dfrac{2}{5}+\left|x+1\right|=\dfrac{3}{4}\)
3. Tìm x, y biết:
a. \(\dfrac{x}{18}=\dfrac{y}{15}\)và x - y = -30
b. 7x = 9x và 10x - 8x = 68
c. \(\left(x-\dfrac{1}{2}\right)^{50}+\left(y+\dfrac{1}{3}\right)^{40}=0\)
* Lm nhanh nha
Tìm số nguyên x biết:
a. \(-4\dfrac{3}{5}.2\dfrac{4}{23}\)<x<\(-2\dfrac{3}{5}:1\dfrac{6}{15}\) b. \(-4\dfrac{1}{3}.\left(\dfrac{1}{2}-\dfrac{1}{6}\right)< x< -\dfrac{2}{3}\left(\dfrac{1}{3}-\dfrac{1}{2}-\dfrac{3}{4}\right)\)
Tinh x:
a)\(\dfrac{3}{4}+\dfrac{1}{4}:x=\dfrac{2}{5}\)
b)\(\dfrac{1}{4}+\dfrac{1}{3}:2x=-5\)
c)\(-2+\left|x+\dfrac{1}{5}\right|=\dfrac{9}{10}\)
1. Tìm x:
a. |x| 5,6 b. |x-3,5| 5 c.|x+dfrac{3}{4}| - dfrac{1}{2} 0 d. |4x| -|-13,5| |dfrac{9}{4}|
e. (x-1)3 27 f. (2x-3)236 g. 5x + 2 625 h. (2x -1) 3 -8
i.* dfrac{1}{4}.dfrac{2}{6}.dfrac{3}{8}.dfrac{4}{10}.dfrac{5}{12}...dfrac{30}{62}.dfrac{31}{64}2^x
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1. Tìm x:
a. |x| = 5,6 b. |x-3,5| = 5 c.|x+\(\dfrac{3}{4}\)| - \(\dfrac{1}{2}\)= 0 d. |4x| -|-13,5| = |\(\dfrac{9}{4}\)|
e. (x-1)3 = 27 f. (2x-3)2=36 g. 5x + 2= 625 h. (2x -1) 3 = -8
i.* \(\dfrac{1}{4}\).\(\dfrac{2}{6}.\dfrac{3}{8}.\dfrac{4}{10}.\dfrac{5}{12}...\dfrac{30}{62}.\dfrac{31}{64}=2^x\)
Tìm x biết :
a)\(\dfrac{x+1}{2x+1}=\dfrac{\dfrac{1}{2}x+2}{x+3}\)
b) \(x^2+5x=0\)
c)\(\dfrac{1}{4}.\dfrac{2}{6}.\dfrac{3}{8}.\dfrac{4}{10}.\dfrac{5}{12}...\dfrac{30}{62}.\dfrac{31}{64}=2^x\)
Bài 2: Tìm x biết:
1) \(\dfrac{x}{12}-\dfrac{5}{6}=\dfrac{1}{12}\) 2) \(\dfrac{2}{3}-1\dfrac{4}{15}x=\dfrac{-3}{5}\) 3) -2\(^3\)+ 0,5x =1,5
câu 1 tìm x biết
\((-1\dfrac{1}{5}+x)\div(-3\dfrac{3}{5})=\dfrac{-7}{4}+\dfrac{1}{4}\div\dfrac{1}{8}\)
\(\dfrac{5}{7}+\dfrac{2}{3}x=\dfrac{3}{10}\)
\(-\dfrac{22}{15}x+\dfrac{1}{3}=|-\dfrac{2}{3}+\dfrac{1}{5}|\)
13 Tìm x, biết :
a) \(\dfrac{2}{3}x+4=-12\); b) \(\dfrac{3}{4}+\dfrac{1}{4}:x=-3\); c) \(\left|3x-5\right|=4\)
d) \(\dfrac{x+1}{10}+\dfrac{x+1}{11}+\dfrac{x+1}{12}=\dfrac{x+1}{13}+\dfrac{x+1}{14}\) ;
e) \(\dfrac{x+4}{2000}+\dfrac{x+3}{2001}=\dfrac{x+2}{2002}+\dfrac{x+1}{2003}\)