25%x+1/2(x-4/5)=2,6
a: x/3,15=0.15/7.2
b: -2,6/x=-12/42
c: x-1/x+5=6/7
d: x/6=24/25
\(\frac{x}{3,15}=\frac{0,15}{7,2}\)
\(\Rightarrow x=\frac{0,15.3,15}{7,2}\)
\(\Rightarrow x=0,065625\)
b) \(\frac{-2,6}{x}=\frac{-12}{42}\)
\(\Rightarrow x=\frac{-2,6.42}{-12}\)
\(\Rightarrow x=9,1\)
Tìm x:
a) x/6 = 7/4
b) 3/x = 21/17
c) 125x = 25/3
d) -3/x = 15/7
e) 0,1/5 = x//15
f) -4/1,2 = x/-3,6
g) -2,6/12 = x/-42
h) 21/14 = 33/x
i) 1,4/-5 = 2,1/x
k) 0,12/3 = 0,21/x
l) x-2/3 = 4/5
n) x+3/-4 = 5/12
m) 3/ x-1 = 21/16
a: x/6=7/4
=>x=7/4x6=42/4=21/2
b: 3/x=21/17
=>21/7x=21/17
=>7x=17
=>x=17/7
d: =>-15/5x=15/7
=>5x=-7
=>x=-7/5
e: =>x/15=0,3/15
=>x=0,3
Tìm x biết
1.35/x=15/12
2.-2,6/x=-12/42
3.125/10=x/45
4.x^2/6=24/25
\(\frac{35}{x}=\frac{15}{12}\Leftrightarrow x=35.12:15=28\)
\(-\frac{2,6}{x}=-\frac{12}{42}\Leftrightarrow\frac{-2,6}{x}=-\frac{2}{7}\Leftrightarrow x=-2,6.7:\left(-2\right)=\frac{91}{10}\)
\(\frac{125}{10}=\frac{x}{45}\Leftrightarrow x=125.45:10=562,5\)
\(\frac{x^2}{6}=\frac{24}{25}\Leftrightarrow x^2=6.24:25=\frac{144}{25}\Leftrightarrow x=\sqrt{\frac{144}{25}}\Leftrightarrow x=\frac{12}{5}\)
1; \(\dfrac{35}{x}\) = \(\dfrac{15}{12}\) (\(x\ne\) 0)
⇒ \(x\) = 35 : \(\dfrac{15}{12}\)
⇒ \(x\) = 28
Vậy \(x=28\)
2; - \(\dfrac{2,6}{x}\) = \(\dfrac{-12}{42}\) (đk \(x\) ≠ 0)
\(x\) = - 2,6 : (\(\dfrac{-12}{42}\))
\(x\) = - \(\dfrac{13}{5}\) : \(\dfrac{-2}{7}\)
\(x\) = - \(\dfrac{13}{5}\) x \(\dfrac{7}{-2}\)
\(x\) = \(\dfrac{91}{10}\)
Vậy \(x\) = \(\dfrac{91}{10}\)
43,57*2,6*(630-315*2)
4/1*3+4/1*5+...+4/13*15
3/4+24%+0,76+25%
4/5*5/4*36%*2,5
a, 17,58 x 43 + 57 x 17,58
b, 43,57 x 2,6 x ( 630 - 315 x 2 )
c, 1996 + 3992 + 5988 + 7984
d, 2 x 3 x 4 x 8 x 50 x 25 x 125
a, 17,58 x 43 + 57 x 17,58
=17,58x(43+57)
=17,58x100
=1758
b, 43,57 x 2,6 x ( 630 - 315 x 2 )
= 43,57 x 2,6 x0
=0
c, 1996 + 3992 + 5988 + 7984
=1996+7984+3992+5988
=9980+9980
=2x9980
=19960
d, 2 x 3 x 4 x 8 x 50 x 25 x 125
=8x125x4x25x6
=1000x100x6
=1000x600
=600000
~~~~~~~~~~~~Ai đi qua nhớ để lại
a) 17,58 x 43 + 57 x 17,58
= 17,58 x ( 43 + 57)
= 17,58 x 100
= 1758
b) 43,57 x 2,6 x ( 630 - 315 x 2 )
=43,57 x 2,6 x 0
= 0
c) 1996 + 3992 + 5988 + 7984
=(1996 + 7984) +( 3992 + 5988)
= 9980 +9980
= 19960
d) (2 x 50) x (4 x 25) x (8 x 125) x 3
= 100 x 100 x 1000 x 3
= 30000000
Tìm x
A,2/3-|x|=1/5
B,|x+1,4|=2,6
C,|x+4/5|-1/7=0
D,(-1/2)^3× x=(-1/2)^5
E,x^2=4
F,(2x-3)^2=16
G,1/9×27^x=3^x
tìm X
a) X + 1/4 = 5/8 + 2/5 b) X : 3/4 = 4/10 - 4/10
c) X + 3,4 x 2,6 = 4,8 x 5,2 d) X : 1,5 + 1,5 = 0,8 x 2
a) X + 1/4 = 5/8 + 2/5
X + 1/4 = 41/10
X = 41/10 - 1/4
X = 31/40
b) X : 3/4 = 4/10 - 4/10
X : 3/4 = 0
X = 0
c) X + 3,4 x 2,6 = 4,8 x 5,2
X + 8,84 = 24,96
X = 24,96 : 8,84
X = 48/17
d) X : 1,5 + 1,5 = 0,8N x 2
= bó tay nhé
12,5*4-x=4,3+2,6
(x+0,9)*(1-0,4)=2412
x+1/4=5/8
3/5-x=3/8
15/7<hỗn số>*x=2 3/6<hỗn số>
29/7-x=3/2
x+3/4=13/8
x*3/4=9/40
x-2/3=2/15
x*1/2=2/3
Tìm số tự nhiên x bé nhất trong các số 2; 3; 4; 5 sao cho 2,6 × x >7
Chọn x = 2 ta được: 2,6 × 2 = 5,2 < 7 (loại)
Chọn x = 3 ta được: 2,6 × 3 = 7,8 > 7
Chọn x = 4 ta được: 2,6 × 4 = 10,4>7
Chọn x = 5 ta được: 2,6 × 5 = 13 > 7
Vậy số tự nhiên bé nhất chọn là x = 3
Nếu x = 2 thì 2,6 x 2= 5,2<7(loại)
Nếu x = 3 thì 2,5 x 3= 7,8>7
Nếu x=4 thì 2,6 x4=10,4>7
Nếu x=5 thì 2,6x5=13>7
Vậy x=3