a) \(210:x=2,1:0,25=8,4\)

\(x=210:8,4=25\)

b) \(x.2+x.0,5=6,25\)

\(2,5x=6,25\)

\(x=6,25:2,5=2,5\)

c) \(x:0,25-x=15,6\)

\(3x=15,6\)

\(x=5,2\)

d) \(x:12,5=3,75.4=15\)

\(x=15.12,5=187,5\)

e) \(x.12,6-x.5,6=42\)

\(7x=42\)

\(x=6\)

g) \(x:0,1-x:4-x.0,75=2,25\)

\(10x-\dfrac{x}{4}-\dfrac{3x}{4}=2,25\)

\(9x=2,25\)

\(x=0,25\)

giúp mình gấp mn

wth khó thế

mn tl hộ e 5p' nữa e phải nộp r

thanks mn nhiều

3.75 : \(\dfrac{1}{4}\) + 3.75 : 0.5 + 3,75 + \(\dfrac{1}{8}\)  + 3,75 x 86

= 3,75 : \(\left(\dfrac{1}{4}+0.5+\dfrac{1}{8}\right)\) + 3,75 x 86

= 3,75 : \(\dfrac{7}{8}\) + 322.5

= 4,3 + 322.5 = 326,8

tích hộ chị nha

\(x\div0,5+x\div0,25+x\div0,125=3,75\)

\(\Leftrightarrow2x+4x+8x=3,75\)

\(\Leftrightarrow x\left(2+4+8\right)=3,75\)

\(\Leftrightarrow14x=3,75\)

\(\Leftrightarrow x=\frac{3,75}{14}\)

\(\Leftrightarrow x=0,2678571\)

\(\text{Vậy }x=0,2678571\)

gfjsdg

\(x\text{ : }0,5+x\text{ : }0,25+x\text{ : }0,125=3,75\)

\(x\text{ x }2+x\text{ x }4+x\text{ x }8=3,75\)

\(x\text{ x }\left(2+4+8\right)=3,75\)

\(x\text{ x }14=3,75\)

\(x=3,75\text{ : }14\)

\(x=\frac{3,75}{14}=0,267857143\)

3,75:0,5+3,75.7-3,75

=3,75x2+3,75x7-3,75x1

=3,75x(2+7-1)

=3,75x8

=30

3,75:0,5+3,75*7-3,75

=3,75*2+3,75*7-3,75*1

=3,75*(2+7-1)

=3,75*8

=30

tick nha

Nhận thấy \(3,75-2,5\times1,5=3,75-3,75=0\)

  NÊN A =\(\left(1995;0,25+1996;4\right)\times2010\times2011\times0\) 

         Vậy A = \(0\) 

A= (1995 : 0,25 + 1996 : 4) . 2010 . 2011 . (3,75 - 2,5 . 1,5)

A=(1995 : 0,25 = 1996 : 4) . 2010 . 2011 . (3,75 - 3,75)

A=(1995 : 0,25 = 1996 : 4) . 2010 . 2011 . 0

A= 0

\(A=\left(\frac{1995}{0,25}+\frac{1996}{4}\right)\cdot2010\cdot2011\cdot\left(3,75-2,5\cdot1,5\right)\)

\(A=\left(\frac{1995}{0,25}+\frac{1996}{4}\right)\cdot2010\cdot2011\cdot\left(3,75-3,75\right)\)

\(A=\left(\frac{1995}{0,25}+\frac{1996}{4}\right)\cdot2010\cdot2011\cdot0\)

\(A=0\)

P/s: cái này là toán mà lại ghi là tiếng Việt kìa, xem lại đi

a=(1995:0,25+1996×4)×2010×2011×(3,75-3,75)

a=(1995:0,25+1996×4)×2010×2011×0

a=0

a: =472x2+472x5+472x2

=472x9=4248

b: =3,6x8+7,2x4+7,2x2

=7,2(4+4+2)

=72

d: =2,4(6,2+1,9x2)=24

a: =472x2+472x5+472x2

=472x9=4248

b: =3,6x8+7,2x4+7,2x2

=7,2(4+4+2)

=72

d: =2,4(6,2+1,9x2)=24

\(\left(84,6-2\cdot x\right):3,02=5,1\)

\(\Rightarrow84,6-2\cdot x=15,402\)

\(\Rightarrow2\cdot x=69,198\)
\(\Rightarrow x=69,198:2\)

\(\Rightarrow x=34,599\)

_____________

\(\left(15\cdot24-x\right):0,25=100:0,25\)

\(\Rightarrow\left(360-x\right):0,25=400\)

\(\Rightarrow360-x=100\)

\(\Rightarrow x-360-100\)

\(\Rightarrow x=260\)

______________

\(128\cdot x-12\cdot x-16\cdot x=5200\)

\(\Rightarrow x\cdot\left(128-12-16\right)=5200\)

\(\Rightarrow x\cdot100=5200\)

\(\Rightarrow x=5200:100\)

\(\Rightarrow x=52\)

__________________

\(5\cdot x+3,75\cdot x+1,25\cdot x=20\)

\(\Rightarrow x\cdot\left(5+3,75+1,25\right)=20\)

\(\Rightarrow10\cdot x=20\)

\(\Rightarrow x=20:10\)

\(\Rightarrow x=2\)

\(x\cdot3,7+x\cdot6,3=360:120\)

\(\Rightarrow x\cdot\left(3,7+6,3\right)=3\)

\(\Rightarrow x\cdot10=3\)

\(\Rightarrow x=\dfrac{3}{10}\)

__________________

\(x\cdot23-6\cdot23+x\cdot69=320\)

\(\Rightarrow x\cdot\left(23+69\right)=320+6\cdot23\)

\(\Rightarrow x\cdot92=458\)

\(\Rightarrow x=458:92\)

\(\Rightarrow x=\dfrac{229}{46}\)

___________________

\(\left(x+1\right)\left(x+2\right)=72\)

\(\Rightarrow x^2+2x+x+2=72\)

\(\Rightarrow x^2+3x+2=72\)

\(\Rightarrow x^2+3x+2-72=0\)

\(\Rightarrow x^2+3x-70=0\)

\(\Rightarrow x^2+10x-7x-70=0\)

\(\Rightarrow\left(x-7\right)\left(x+10\right)=0\)

\(\Rightarrow\left[{}\begin{matrix}x=7\\x=-10\end{matrix}\right.\)

___________________

\(\left(x+2\right)\cdot16\cdot x=160x\)

\(\Rightarrow16x^2+32x=160x\)

\(\Rightarrow16x^2+32x-160x=0\)

\(\Rightarrow16x^2-128x=0\)

\(\Rightarrow16x\left(x-8\right)=0\)

\(\Rightarrow\left[{}\begin{matrix}x=0\\x=8\end{matrix}\right.\)

Đổi:

f.x.23-6.23+x.69=230

=>23.(x-6+3x)=230

=>4x-6=10

=>4x=10+6

=>4x=16

=>x=4

h.(x+2).16.x=160.x

=>(16x+32).x = 160x

=>16x^2 + 32x = 160x

=>16x^2 = 128x

=>16x^2 - 128x=0

=>x(16x-128)=0

=>x=0 hoặc 16x-128=0

+)x=0=>x=0

+)16x-128=0

=>16x=128

=>x=8

:)))))))