Question

[Phạm Trung Nguyên]

Câu 3. Giải các phương trình sau bằng cách đưa về dạng ax+b= 0

1. a, 3x-2=2x-3; b, 3-4y+24+6y=y+27+3y

c, 7-2x=22-3x; d, 8x-3=5x+12

e, x-12+4x=25+2x-1; f, x+2x+3x-19=3x+5

g, 11+8x-3=5x-3+x; h, 4-2x+15=9x+4-2

2. a, 5-(x-6)=4(3-2); b, 2x (x+2)²-8x²=2(x-2) (x²+2x-4)

c, 7-(2x+4)=-(x+4); d, (x-2)³+(3x-1) (3x+1)=(x+1)³

e, (x+1) (2x-3)=(2x-1) (x+5); f, (x-1)³-x(x+1)²=5x (2-x)-11 (x+2)

g, (x-1)-(2x-1)=9-x; h, (x-3) (x+4)-2(3x-2)=(x-4)²

i, x(x+3)²-3x=(x+2)³+1; j, (x+1) (x²-x+1)-2x=x(x+1) (x-1)

3. a, 1,2-(x-0,8)=-2(0,9+x); b, 3,6-0,5 (2x+1)=x-0,25 (2-4x)

c, 2,3x-2 (0,7+2x)= 3,6-1,7x; d, 0,1-2 (0,5t-0,1)=2 (t-2,5)-0,7

e, 3+2,25x+2,6= 2x+5+0,4x; f, 5x+3,48-2,35x= 5,38-2,9x+10,42

Answer 1

[✟şin❖]

Copy có khác, ko đọc đc j!!! ʌl

Câu 3:

1)

a) Ta có:

hay x=-1

Vậy: x=-1

b) Ta có:

hay y=0

Vậy: y=0

c) Ta có:

hay x=15

Vậy: x=15

d) Ta có:

Vì 3≠0

nên x-5=0

hay x=5

Vậy: x=5

Answer 2

[Hoàng Ngọc Anh]

a) 3x - 2 = 2x - 3

\(\Leftrightarrow\) 3x - 2 - 2x + 3 = 0

\(\Leftrightarrow\) x + 1 = 0

\(\Rightarrow\) x = -1

b) 3 - 4y + 24 + 6y = y + 27 + 3y

\(\Leftrightarrow\) 3 - 4y + 24 + 6y - y - 27 - 3y = 0

\(\Leftrightarrow\) -2y = 0

\(\Rightarrow\) y = 0

c)7 - 2x = 22 - 3x

\(\Leftrightarrow\) 7 - 2x - 22 + 3x = 0

\(\Leftrightarrow\) -15 + x = 0

\(\Rightarrow\) x = 15

d) 8x - 3 = 5x + 12

\(\Leftrightarrow\) 8x - 3 - 5x - 12 = 0

\(\Leftrightarrow\)3x -15 = 0

\(\Leftrightarrow\) 3x = 15

\(\Rightarrow\) x = 5

e) x - 12 + 4x = 25 + 2x - 1

\(\Leftrightarrow\) x - 12 + 4x - 25 - 2x + 1 = 0

\(\Leftrightarrow\) 3x - 36 = 0

\(\Leftrightarrow\) 3x = 36

\(\Rightarrow\) x = 12

f ) x + 2x + 3x - 19 = 3x + 5

\(\Leftrightarrow\) x + 2x + 3x - 19 - 3x - 5 = 0

\(\Leftrightarrow\)3x - 24 = 0

\(\Leftrightarrow\) 3x = 24

\(\Rightarrow\) x = 8

g) 11+ 8x - 3 = 5x - 3 +x

\(\Leftrightarrow\)8x + 8 = 6x - 3

\(\Leftrightarrow\)8x - 6x = -3 - 8

\(\Leftrightarrow\)2x = -11

\(\Rightarrow\)x = \(-\frac{11}{2}\)

h) 4 - 2x +15 = 9x + 4 -2

\(\Leftrightarrow\)19 - 2x = 7x + 4

\(\Leftrightarrow\)-2x - 7x = 4 - 19

\(\Leftrightarrow\)-9x = -15

\(\Rightarrow\)x = \(\frac{15}{9}\) = \(\frac{5}{3}\)