1.Tìm x thuộc Q
a. 11/12 - ( 2/5 + x ) = 2/3
2/5 + x = 11/12 - 2/3
2/5 + x = 1/4
x = -3/20
b. 3/4 + 1/4 : x = 2/3
1/4 : x = 2/3 - 3/4
1/4 : x = -1/12
x = 1/4 : -1/12
x = -3
Tìm x biết :
a) \(-\frac{2}{3}.x+4=-12\)
b) \(-\frac{3}{4}+\frac{1}{4}:x=-3\)
c) \(\frac{x+1}{2}+\frac{x+2}{3}+\frac{x+1}{4}=\frac{x+1}{5}+\frac{x+1}{6}\)
d)\(\frac{x+1}{2009}+\frac{x+2}{2008}+\frac{x+3}{2007}=\frac{x+10}{2000}+\frac{x+11}{1999}+\frac{x+12}{1998}\)
Tìm x ϵ Q, biết rằng:
a) 11/12- (2/5+x)=2/3
b) 3/4+1/4:x=2/3
giúp mk nhé thanks trc ! mai mk phải nộp bài r
tìm x ϵ Q , biết rằng:
a) \(\frac{11}{12}-\left(\frac{2}{5}+x\right)=\frac{2}{3}\) B) \(\frac{3}{4}+\frac{1}{4}:x=\frac{2}{3}\)
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) \(\dfrac{x+4}{2000}+\dfrac{x+3}{2001}=\dfrac{x+2}{2002}+\dfrac{x+1}{2003}\)
Tìm x thuộc Q, biết rằng:
a, 11/12 - ( 2/5 + x ) = 2/3
b, 2x . ( x - 1/7 ) = 0
c, 3/4 + 1/4 : x = 2/5
Tìm x thuộc Q biết:
a) 6,5 - \(\frac{9}{4}\): |x+\(\frac{1}{3}\)| = |-2|
b) 2 - |\(\frac{3}{2}x-\frac{1}{4}\)| = |\(-\frac{5}{4}\)|
c) |2x - 3| - |3x+2| = 0
d) |x - 2| + |x - 5| = 6
e) |x - 3| + |x + 5| = 8
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
1. Tính hợp lí :
a) \(\frac{3}{4}-0,25-\left[\frac{7}{3}+\left(\frac{-9}{2}\right)\right]-\frac{5}{6}\)
b) 7 + \(\left(\frac{7}{12}-\frac{1}{2}+3\right)-\left(\frac{1}{12}+5\right)\)
2. Tìm các sô nguyên x biết:
\(\frac{3}{4}-\frac{5}{6}\le\frac{x}{12}< 1-\left(\frac{2}{3}-\frac{1}{4}\right)\)
Bài 1) Tìm x biết
a) |x-\(\frac{1}{3}\)| < \(\frac{5}{3}\)
b) |x+\(\frac{11}{2}\)| > 5
Bài 2) Tìm x biết
a) (x-2)2 =1
b) (2x-1)3 = -27
c) \(\frac{16}{2^x}\) = 1
d) ( x+\(\frac{1}{2}\) )2 = \(\frac{4}{25}\)
e) ( x-1)x+2 = (x-1)x+6 ( x thuộc Z )
f) \(\sqrt{x}\) = 4
g) \(\sqrt{x+1}\) = 5
i) ( x-2 )2 + ( y-3 )2 =0
Làm nhanh giúp mình nha mình đang cần gấp