a, 36:{336:[200–(12+8.20)]}

= 36:{336:[200–(12+160)]}

= 36:{336:[200–172]}

= 36:{336:28}

= 36:12 = 3

b, {145–[130–(246–236)]:2}.5

= {145–[130–10:2]}.5

= {145–130}.5

= 20.5 = 100

c, 100:{250:[450–(4. 5 3 – 2 2 .25]}

= 100:{250:[450–400]}

= 100:{250:50}

= 100:5 = 20

d, 798+100:[16–2.( 5 2 –22)]

= 798+100:10

= 798+10 = 808

e, (6954+1525:5+47.19).(29–58.2)

= (6954+1525:5+47.19).0 = 0

f,  2 4 .157– 2 4 .58+16

= 16.(157–58+1) = 1600

bài 1 

gọi số cần tìm là A

ta có : A=60. q +31

 A=12.17+r (0<r <12)

ta thấy 60. q chia hết cho 12 

ta có 31:12 =2 (dư 7)

=> r=7

A=12.17+7

A=204+7  

A=211

bài 2

b) (4x+ 5) :3 -121 :11 =4

 (4x+5):3-11 =4

(4x+5):3 =4+11

(4x+5) :3=15

4x+5 =15.3

4x+5 =45

4x =45-5

4x=40

x=40:4

x=10

a) \(3\left(x-1\right)^2\cdot3x\left(x-5\right)=0\)

\(\Rightarrow9x\left(x-1\right)^2\left(x-5\right)=0\)

\(\Rightarrow\left[{}\begin{matrix}x=0\\x-1=0\\x-5=0\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=0\\x=1\\x=5\end{matrix}\right.\)

b) \(\left(x+3\right)^2-5x-15=0\)

\(\Rightarrow\left(x+3\right)^2-5\left(x+3\right)=0\)

\(\Rightarrow\left(x+3\right)\left(x+3-5\right)=0\)

\(\Rightarrow\left(x+3\right)\left(x-2\right)=0\)

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

c) \(2x^5-4x^3+2x=0\)

\(\Rightarrow2x\left(x^4-2x^2+1\right)=0\)

\(\Rightarrow2x\left[\left(x^2\right)^2-2\cdot x^2\cdot1+1^2\right]=0\)

\(\Rightarrow2x\left(x^2-1\right)^2=0\)

\(\Rightarrow2x\left(x-1\right)^2\left(x+1\right)^2=0\)

\(\Rightarrow\left[{}\begin{matrix}x=0\\x-1=0\\x+1=0\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=0\\x=1\\x=-1\end{matrix}\right.\)

\(\text{#}Toru\)

Mọi người giúp em với em đang cần gấp!!

Câu 1:

\(a,=43\cdot\left(27+93\right)+3111+3363=43\cdot120+6474=11634\\ b,=11^2+2^{15}\cdot2^3:2^{17}=121+2=123\\ c,=11^2+7^2-9=121+49-9=151\)

Câu 2:

\(a,\Rightarrow x-\dfrac{3}{2}=5^2=25\\ \Rightarrow x=25+\dfrac{3}{2}=\dfrac{53}{2}\\ b,\Rightarrow7x=30-2=28\\ \Rightarrow x=4\)

a) \(70-\left(x-3\right)=45\)

\(x-3=70-45\)

\(x-3=25\)

\(x=25+3\)

\(x=28\)

b) \(12+\left(5+x\right)=20\)

\(5+x=20-12\)

\(5+x=8\)

\(x=8-5\)

\(x=3\)

c) \(130-\left(100+x\right)=25\)

\(100+x=130-25\)

\(100+x=105\)

\(x=105-100\)

\(x=5\)

d) \(175+\left(30-x\right)=200\)

\(30-x=200-175\)

\(30-x=25\)

\(x=30-25\)

\(x=5\)

e) \(\left(x+12\right)+22=92\)

\(x+12=92-22\)

\(x+12=70\)

\(x=70-12\)

\(x=58\)

f) \(95-\left(x+2\right)=45\)

\(x+2=95-45\)

\(x+2=50\)

\(x=50-2\)

\(x=48\)

a)

70 - (x - 3) = 45

x - 3 = 70 - 45 = 25

x = 25 + 3 = 28

Vậy x = 28

b)

12 + (5 + x) = 20

5 + x = 20 - 12 = 8

x = 8 - 5 = 3

Vậy x = 3

c)

130 - (100 + x) = 25

100 + x = 130 - 25 = 115

x = 115 - 100 = 15

Vậy x = 15

d)

175 + (30 - x) = 200

30 - x = 200 - 175 = 25

x = 30 - 25 = 5

Vậy x = 5

e)

(x + 12) + 22 = 92

x + 12 = 92 - 22 = 70

x = 70 - 12 = 58

Vậy x = 58

f)

95 - (x + 2) = 45

x + 2 = 95 - 45 = 50

x = 50 - 2 = 48

Vậy x = 48

a) x + 20 chia hết cho x + 2

=> x + 2 + 18 chia hết cho x + 2

=> 18 chia hết cho x + 2

Bạn liệt kê ra nhé         

gúp minh với ạ 

a) \(70-5\left(x-3\right)=45\)

\(5\left(x-3\right)=25\)

\(x-3=5\)

\(\Rightarrow x=8\)

b) \(12+\left(5+x\right)=20\)

\(5+x=8\)

\(\Rightarrow x=3\)

c) \(130-\left(100+x\right)=25\)

\(100+x=105\)

\(\Rightarrow x=5\)

d) \(175+\left(30-x\right)=200\)

\(30-x=25\)

\(\Rightarrow x=5\)

e) \(5\left(x+12\right)+22=92\)

\(5\left(x+12\right)=70\)

\(x+12=14\)

\(\Rightarrow x=2\)

a. 70 - 5.(x - 3) = 45

5.(x - 3)             = 70 - 45

x - 3                  = 25 : 5

x                       = 5 + 3

x                       = 8

b. 12 + (5 + x) = 20

5 + x               = 20 - 12

x                     = 8 - 5

x                     = 3

c. 130 - (100 + x) = 25

100 + x                = 130 - 25

x                          = 105 - 100

x                         = 5

d. 175 + (30 - x) = 200

30 - x                 = 200 - 175

x                        = 30 - 25

x                        = 5

e. 5.(x + 12) + 22 = 92

5.(x + 12)             = 92 - 22

x + 12                  = 70 : 5

x                          = 14 - 12

x                          = 2