1000 + x = 20 + 20

1000 + x = 40

           x = 1000 - 40

           x = 960

tính nhanh

50 x 2 + 50 x 2 = 200

\(1000+x=20+20\)

\(1000+x=40\)

                \(x=40-1000\)

                \(x=-960\)

\(50x2+50x2\)

\(=50x\left(2+2\right)\)

\(=50x4\)

\(=200\)

\(K\)\(nha\)\(ban!!!\)

   1000 + x = 20 + 20 
= 1000 + x = 40
= 40 - 1000
= -960

   50 x 2 + 50 x 2
= 100 + 100
= 200

50.(x+20) = 2

=> x + 20 = 1/25

=> x = 1/25 - 20

=> x = -499/25 

50.(x+20)=2

<=>(x+20)=50:2

<=>x+20=25

<=>x=25-20

<=>x=5

Vậy x = 5

\(50+90=90+50=140\)

\(90+600=600+90=690\) .

\(x:2=50+20\)

\(\frac{x}{2}=70\)

 \(x=70.2=140\)

\(x+25=\frac{100}{25}\)

\(x+25=4\)

\(x=4-25\)

\(x=-21\)

50 + 90 = 90 + 50

90 + 600 = 600 + 90

Tìm x 

x : 2 = 50 + 20

x : 2 = 70

x = 70 * 2

x = 140

x + 25 = 50 *2

x + 25 = 100

x = 100 - 25

x = 75

50+90 = 140

90+ 600= 690

x : 2 = 50+20

x : 2 = 70

x      = 70:2

x     = 35

x + 25 = 100 : 25

x + 25 = 4

x        = 25+4

x        = 29

k mình đúng nhea :>

Câu 1 : nhẩm ra cũng pit x= -19

Bài toán sai

bài toán đúng là x+(x+1)+(x+2)+(x+3)+...+19+20=20

\(\left(x_1+x_2\right)+\left(x_3+x_4\right)+...+\left(x_{49}+x_{50}\right)+\left(x_{50}+x_{51}\right)\)=\(1+x_{50}\)

\(1+1+...+1+1=1+x_{50}\)

\(1+1+...+1+1=26\)(vì ta có 52 số hạng gồm thêm \(x_{50}\))

\(26=1+x_{50}\)

\(\Rightarrow25=x_{50}\)

\(450:\left(x-19\right)=50\\ \Leftrightarrow x-19=5\\ \Leftrightarrow x=24\)

\(2\left(x-52\right)=2.23+20\\ \Leftrightarrow2\left(x-52\right)=66\\ \Leftrightarrow x-52=33\\ \Leftrightarrow x=85\)

\(10-\left(x-3\right):2=72-100\\ \Leftrightarrow10-\left(x-3\right):2=-28\\ \Leftrightarrow10-\left(x-3\right)=-56\\ \Leftrightarrow x-3=66\\ \Leftrightarrow x=69\)

1.x-19=450:50

   x-19=9

  x      =9+19

 x        =28

2. 2(x-51)=46+20

    2(x-51)=66

       x-51=66:2

       x-51=33

       x      =33+51

       x       =84

`@` `\text {Ans}`

`\downarrow`

`a,`

`(x-1954) \times 5=50`

`x-1954 = 50 \div 5`

`x-1954 = 10`

`x=10 + 1954`

`x= 1964`

`B.`

`48 - 40 \times x=8`

`40 \times x=48-8`

`40 \times x = 40`

` x=40 \div 40`

`x=1`

`C.`

`2+70 \div x = 3`

`70 \div x = 3-2`

`70 \div x = 1`

`x=70 \div 1`

`x=70`

`D. [3 \times (x+2) \div 7]  \times  4=120`

`3 \times (x+2) \div 7 = 120 \div 4`

`3 \times (x+2) \div 7 =30`

`3 \times (x+2) = 30 \times 7`

`3 \times (x+2)=210`

`x+2=210 \div 3`

`x+2=70`

`x=70-2`

`x=68`

`E.`

`7,2 \div [ (0,6 \times x+8) \div 20 + 59] = 0,12?` Thiếu ngoặc bạn nhé._.

\(a,\left(x-1954\right)\times5=50\\ x-1954=50:5\\ x-1954=10\\ x=1954+10\\ x=1964\\b.48-40\times x=8\\40\times x=48-8\\40\times x=40\\ x=40:40\\ x=1 \\ c.2+70:X=3\\ 70:x=3-2\\ 70:x=1\\ x=70:1\\ x=70\\ d,\left[3\times\left(x+2\right):7\right]\times4=120\\ 3\times\left(x+2\right):7-120:4\\ 3\times\left(x+2\right):7=30\\ \left(x+2\right):7=30:3\\ \left(x+2\right):7=10\\ x+2=10\times7\\ x+2=70\\ x=70-2\\ x=68\)