Tìm số nguyên x, biết:
1) -16 + 23 + x = - 16

7+x=-16

    x=-16-7

    x=-23
2) 2x – 35 = 15

2x=15+35

2x=50

  x=50:2

  x=25
3) 3x + 17 = 12

3x=12-17

3x=-5

  x=-5/3
4) (2x – 5) + 17 = 6

2x-5=6-17

2x-5=-11

2x=-11+5

2x=-6

  x=-6:2

  x=-3
5) 10 – 2(4 – 3x) = -4

2(4-3x)=10-(-4)

2(4-3x)=14

4-3x=14:2

4-3x=7

3x=4-7

3x=-3

  x=-3:3

  x=-1
6) - 12 + 3(-x + 7) = -18

3(-x+7)=-18-(-12)

3(x+7)=-6

x+7=-6:3

x+7=-2

    x=-2-7

    x=-9

tự đi mà làm

a) 71 + \(\frac{26-3x}{5}=75\)

↔ \(\frac{26-3x}{5}=4\)

↔\(26-3x=20\)

↔x=2

b) \(x-17=\left(-8\right)-17\)

↔ \(x-17=-25\)

↔\(x=-8\)

c)\(\left(5x-2\right).6^3=3.6^5\)

↔\(\left(5x-2\right)=3.6^2\)

↔\(5x=110\)

↔\(x=22\)

d)\(\left(3x-2^4\right).7^3=2.7^4\)

↔\(3x-16=14\)

↔x=10

tick nha~~

Mình trả lời hai câu đầu trước nha!

1)

x= -6+2

x= -4

2)

=-5 x = 13 + (-3)

= -5 .x =10

x = 10 ÷ -5

x = -2

Lời giải:

$45-5(x+4)=10$

$5(x+4)=45-10=35$

$x+4=35:5=7$

$x=7-4=3$

------------------------

$(7x-15):3-6=17$

$(7x-15):3=17+6=23$
$7x-15=23\times 3=69$

$7x=69+15=84$

$x=84:7=12$

------------------

$3^{x+2}-5.3^x=108$

$3^x(3^2-5)=108$

$3^x.4=108$

$3^x=108:4=27=3^3$

$\Rightarrow x=3$

\(45-5\left(x+4\right)=10\)

\(\Rightarrow5\left(x+4\right)=45-10\)

\(\Rightarrow5\left(x+4\right)=35\)

\(\Rightarrow x+4=35:5\)

\(\Rightarrow x+4=7\)

\(\Rightarrow x=7-4\)

\(\Rightarrow x=3\)

______________

\(\left(7x-15\right):3-6=17\)

\(\Rightarrow\left(7x-15\right):3=17+6\)

\(\Rightarrow\left(7x-15\right):3=23\)

\(\Rightarrow7x-15=23\cdot3\)

\(\Rightarrow7x-15=69\)

\(\Rightarrow7x=69+15\)

\(\Rightarrow7x=84\)

\(\Rightarrow x=12\)

______________

\(3^{x+2}-5\cdot3^x=108\)

\(\Rightarrow3^x\cdot\left(3^2-5\right)=108\)

\(\Rightarrow3^x\cdot\left(9-5\right)=108\)

\(\Rightarrow3^x\cdot4=108\)

\(\Rightarrow3^x=108:4\)

\(\Rightarrow3^x=27\)

\(\Rightarrow3^x=3^3\)

\(\Rightarrow x=3\)

_Thần đồng ngu học (Toàn bài dễ)

a) x/7 = 6/21

x/7 = 2/7

=>x=2

b)2/3x -1/2=1/10

2/3x = 1/10+1/2

2/3x = 3/5

x=3/5:2/3

x=9/10

c)1/4+1/3 : x = -5

d)3x+17=2

đ)2/3x +1/4 =7/12

2x+3/10= 11/6 . 6/11

x : 4 1/3 = -2,5

a) x/7 = 6/21

x/7 = 2/7

=>x=2

b)2/3x -1/2=1/10

2/3x = 1/10+1/2

2/3x = 3/5

x=3/5:2/3

x=9/10

c)1/4+1/3 : x = -5

d)3x+17=2

đ)2/3x +1/4 =7/12

2x+3/10= 11/6 . 6/11

x : 4 1/3 = -2,5

x + 3x + 4x + 3x + 1 = 0

⇒x + x + 2x + 2x + 2x + 2x + x + 1 = 0

⇒x x + 1 + 2x x + 1 + 2x x + 1 + x + 1 = 0 ⇒ x + 1 x + x + x + x + x + 1 = 0 ⇒ x + 1 x x + 1 + x x + 1 + x + 1 = 0 ⇒ x + 1 x + 1 x + x + 1 = 0 ⇒ x + 1 x + x + 1 = 0 ⇒ x + 1 = 0 vix̀ + x + 1 ≠ 0 ⇒x + 1 = 0 ⇒x = −1 vậy pt có No ......... 3 2x − 3 − 6 x − 3 = 5 4x + 3 − 17 ⇔ 30 10 2x − 3 − 30 5 x − 3 = 30 6 4x + 3 − 30 17.30 ⇔20x − 30 − 5x + 15 = 24x + 18 − 510 ⇔20x − 5x − 24x = 18 − 510 + 30 − 15

⇔− 9x = −477 ⇔x = 53

vậy pt có No........

\(x^4+3x^3+4x^2+3x+1=0\)

\(\Rightarrow x^4+x^3+2x^3+2x^2+2x^2+2x+x+1=0\)

\(\Rightarrow x^3\left(x+1\right)+2x^2\left(x+1\right)+2x\left(x+1\right)+\left(x+1\right)=0\)

\(\Rightarrow\left(x+1\right)\left(x^3+x^2+x^2+x+x+1\right)=0\)

\(\Rightarrow\left(x+1\right)\left[x^2\left(x+1\right)+x\left(x+1\right)+\left(x+1\right)\right]=0\)

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

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

\(\Rightarrow\left(x+1\right)^2=0\left(vìx^2+x+1\ne0\right)\)

\(\Rightarrow x+1=0\)

\(\Rightarrow x=-1\)

vậy pt có No .........

\(\frac{2x-3}{3}-\frac{x-3}{6}=\frac{4x+3}{5}-17\)

\(\Leftrightarrow\frac{10\left(2x-3\right)}{30}-\frac{5\left(x-3\right)}{30}=\frac{6\left(4x+3\right)}{30}-\frac{17.30}{30}\)

\(\Leftrightarrow20x-30-5x+15=24x+18-510\)

\(\Leftrightarrow20x-5x-24x=18-510+30-15\)

\(\Leftrightarrow-9x=-477\)

\(\Leftrightarrow x=53\)

vậy pt có No........

a) \(\dfrac{2}{3}x-\dfrac{1}{2}=\dfrac{1}{10}\)

\(\dfrac{2}{3}x=\dfrac{1}{10}+\dfrac{1}{2}=\dfrac{3}{5}\)

\(x=\dfrac{3}{5}:\dfrac{2}{3}=\dfrac{9}{10}\)

b) \(\dfrac{39}{7}:x=13\)

\(x=\dfrac{\dfrac{39}{7}}{13}=\dfrac{3}{7}\)

c) \(\left(\dfrac{14}{5}x-50\right):\dfrac{2}{3}=51\)

\(\dfrac{14}{5}x-50=51\cdot\dfrac{2}{3}=34\)

\(\dfrac{14}{5}x=34+50=84\)

\(x=\dfrac{84}{\dfrac{14}{5}}=30\)

d) \(\left(x+\dfrac{1}{2}\right)\left(\dfrac{2}{3}-2x\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x+\dfrac{1}{2}=0\\\dfrac{2}{3}-2x=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=-\dfrac{1}{2}\\x=\dfrac{1}{3}\end{matrix}\right.\)

e) \(\dfrac{2}{3}x-\dfrac{1}{2}x=\dfrac{5}{12}\)

\(\dfrac{1}{6}x=\dfrac{5}{12}\)

\(x=\dfrac{5}{12}:\dfrac{1}{6}=\dfrac{5}{2}\)

g) \(\left(x\cdot\dfrac{44}{7}+\dfrac{3}{7}\right)\dfrac{11}{5}-\dfrac{3}{7}=-2\)

\(\left(x\cdot\dfrac{44}{7}+\dfrac{3}{7}\right)\cdot\dfrac{11}{5}=-2+\dfrac{3}{7}=-\dfrac{11}{7}\)

\(x\cdot\dfrac{44}{7}+\dfrac{3}{7}=-\dfrac{11}{7}:\dfrac{11}{5}=-\dfrac{5}{7}\)

\(\dfrac{44}{7}x=-\dfrac{5}{7}-\dfrac{3}{7}=-\dfrac{8}{7}\)

\(x=-\dfrac{8}{7}:\dfrac{44}{7}=-\dfrac{2}{11}\)

h) \(\dfrac{13}{4}x+\left(-\dfrac{7}{6}\right)x-\dfrac{5}{3}=\dfrac{5}{12}\)

\(\dfrac{25}{12}x-\dfrac{5}{3}=\dfrac{5}{12}\)

\(\dfrac{25}{12}x=\dfrac{5}{12}+\dfrac{5}{3}=\dfrac{25}{12}\)

\(x=1\)

Mỏi tay woa bn làm nốt nha!!

\(a.17+8x=10-6x\\\Leftrightarrow 8x+6x=-17+10\\\Leftrightarrow 2x=-7\\ \Leftrightarrow x=-\frac{7}{2}\)

Vậy nghiệm của phương trình trên là \(-\frac{7}{2}\)

\(b.3\left(x+5\right)+7=19-5\left(x-2\right)\\\Leftrightarrow 3x+15+7=19-5x+10\\ \Leftrightarrow3x+5x=-15-7+19+10\\ \Leftrightarrow8x=7\\\Leftrightarrow x=\frac{7}{8}\)

Vậy nghiệm của phương trình trên là \(\frac{7}{8}\)

\(c.3x-4\left(x+2\right)\left(x+3\right)=14-4\left(x^2-3x\right)\\ \Leftrightarrow3x-4\left(x^2+5x+6\right)=14-4x^2+12x\\ \Leftrightarrow4x^2-4x^2+3x-5x-12x=24+14\\ \Leftrightarrow-14x=38\\ \Leftrightarrow x=-\frac{19}{7}\)

Vậy nghiệm của phương trình trên là \(-\frac{19}{7}\)

\(d.x+\frac{3}{4}+3x+2=\frac{x}{3}-3x-\frac{2}{6}\\ \Leftrightarrow\frac{12x}{12}+\frac{9}{12}+\frac{36x}{12}+\frac{24}{12}=\frac{4x}{12}-\frac{36x}{12}-\frac{4}{12}\\ \Leftrightarrow12x+9+36x+24=4x-36x-4\\ \Leftrightarrow12x+36x+36x-4x=-24-9-4\\ \Leftrightarrow80x=-37\\ \Leftrightarrow x=-\frac{37}{80}\)