a.x-25=0+110

   x+25=110

   x=85

b.118-x=142-124

   118-x=18

   x=100

c.3x+22=124-42

3x+22=82

3x=88-22

3x=66

x=22

d.x-2=18

x=20

e.x-32=18.16

x-32=288

x=320

f.19-2x=294:42

19-2x=7

2x=19-7

2x=12

x=6

Dung thi k cho minh nha!!!

124+(118-x)=142

   42 x 3 + 18 x 32 + 18 x 61

= 6 x 7 x 3 + 18 x 32 + 18 x 61

= 18 x 7 + 18 x 32 + 18  x 61

= 18 x (7 + 32 + 61)

= 18 x 100

= 1800

\(42\times3+18\times32+18\times61\)

\(=6\times7\times3+18\times32+18\times61\)

\(=18\times7+18\times32+18\times61\)

\(=18\times\left(7+32+61\right)\)

\(=18\times100\)

\(=1800\)

6 x 7 x 3 + 18 x 32 +18 x 61

18 x 7 + 18 x32 +18 x 61

18 x ( 7 + 32 + 61 )

18 x           100

1800

`#3107.101107`

a,

$2014^{15} . (2x - 60) = 2014^{16}$

$\Rightarrow 2x - 60 = 2014^{16} \div 2014^{15}$

$\Rightarrow 2x - 60 = 2014$

$\Rightarrow 2x = 2074$

$\Rightarrow x = 1037$

Vậy, `x = 1037`

b,

`x + 18 \div 3^2 = 5.4^2`

`\Rightarrow x + 18 \div 9 = 5.16`

`\Rightarrow x + 9 = 80`

`\Rightarrow x = 80 - 9`

`\Rightarrow x = 71`

Vậy, `x = 71`

c,

`7.(42 - x) = 5^3 + 134`

`\Rightarrow 7.(42 - x) = 125 + 134`

`\Rightarrow 7(42 - x) = 259`

`\Rightarrow 42 - x = 259 \div 7`

`\Rightarrow 42 - x = 37`

`\Rightarrow x = 42 - 37`

`\Rightarrow x = 5`

Vậy, `x = 5.`

\(2,\)

\(a,20-\left[4^2+\left(x-6\right)\right]=90\)

\(\Rightarrow20-16-x+6=90\)

\(\Rightarrow10-x=90\)

\(\Rightarrow x=-80\)

Vậy: \(x=-80\)

\(b,\left(x+3\right)\left(2x-4\right)=0\)

\(\Rightarrow\left[{}\begin{matrix}x+3=0\\2x-4=0\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}x=-3\\x=2\end{matrix}\right.\)

Vậy: \(x\in\left\{-3;2\right\}\)

\(c,1000:\left[30+\left(2^x-6\right)\right]=3^2+4^2\left(x\in N\right)\)

\(\Rightarrow1000:\left(30+2^x-6\right)=25\)

\(\Rightarrow24+2^x=40\)

\(\Rightarrow2^x=16\)

\(\Rightarrow x=4\)

Vậy: \(x=4\)

:))))

\(2,\)

\(a,20-\left[42+\left(x-6\right)\right]=90\)

\(\Rightarrow20-42-x+6-90=0\)

\(\Rightarrow x=-106\)

Vậy: \(x=-106\)

\(b,\left(x+3\right)\left(2x-4\right)=0\)

\(\Rightarrow\left[{}\begin{matrix}x+3=0\\2x-4=0\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}x=-3\\x=2\end{matrix}\right.\)

Vậy: \(x\in\left\{-3;2\right\}\)

\(c,1000:\left[30+\left(2x-6\right)\right]=32+42\left(x\in N\right)\)

\(\Rightarrow1000:\left(30+2x-6\right)=74\)

\(\Rightarrow1000:\left(24+2x\right)=74\)

\(\Rightarrow24+2x=\dfrac{500}{37}\)

\(\Rightarrow2x=-\dfrac{388}{37}\)

\(\Rightarrow x=-\dfrac{194}{37}\)

Mà \(x\in N\)

\(\Rightarrow x\in\varnothing\)

Vậy: \(x\in\varnothing\)

a) 32 : 4 : 2 = 8 : 2 = 4 

     32 : 4 : 2 = 32 : 2 = 16 

b) 18 : 2 x 3 = 18 : 6 = 3

     18 : 2 x 3 = 9 x 3 = 18