a , 2x -3 = 5x + 6
2x -5x=6+3
-3x = 9
x =9 :(-3)
x= -3
a) 2x-5x=3+6
-3x=9
x=-3
vậy........
b)(2x+1).(3x-2)-(5x-8).(2x+1)=0
(2x+1).(3x-2-2x-1)=0
(2x-1).(x-3)=0
==>x=1/2 ; x=3
c)(2x+1).5-(7x+5)=(2x-2).3
10x+5-7x-5=6x-6
3x=6x-6
3x-6x=6
-3x=6
x=-2
a) 2x - 3 = 5x + 6
<=> -3x = 9
<=> x = -3
b) (2x + 1).(3x - 2) = (5x - 8).(2x + 1)
<=> 6x2 - 4x + 3x - 2 = 10x2 + 5x - 16x -8
<=> -4x2 - 10x + 6 = 0
<=> \(\orbr{\begin{cases}x=\frac{1}{2}\\x=-3\end{cases}}\)
c) \(\frac{2\text{x}+1}{3}-\frac{7\text{x}+5}{15}=\frac{2\text{x}-2}{5}\)
<=> \(\frac{5.\left(2\text{x}+1\right)}{5.3}-\frac{7\text{x}+5}{15}=\frac{3.\left(2\text{x}-2\right)}{3.5}\)
<=> 10x + 5 - 7x + 5 - 6x + 6 = 0
<=> -3x + 16 = 0
<=> -3x = -16
<=> x = \(\frac{16}{3}\)
d) \(\frac{3x}{x-2}-\frac{x}{x-5}=\frac{3\text{x}}{\left(x-2\right).\left(5-x\right)}\)
<=> \(\frac{3\text{x}\left(x-5\right)-x\left(x-2\right)}{\left(x-2\right).\left(5-x\right)}=\frac{3\text{x}}{\left(x-2\right).\left(5-x\right)}\)
<=> 3x2 - 15x - x2 + 2x - 3x = 0
*Câu e dễ quá, bạn tự làm nhé :v*
a) 2x-3=5x+6 hay -9=3x nên x=-3
b) (2x+1)(3x-2-5x+8)=0e4
hay (2x+1)(6-2x)=0
nên x=-0.5 hoặc x=3
c) \(\frac{2x+1}{3}-\frac{7x+5}{15}=\frac{2x-2}{5}\Rightarrow10x+5-7x-5=6x-6\Leftrightarrow x=2\)
d)\(\frac{3x}{x-2}+\frac{x}{5-x}=\frac{3x}{\left(x-2\right)\left(5-x\right)}\Leftrightarrow\frac{3x\left(5-x\right)+x\left(x-2\right)}{\left(x-2\right)\left(5-x\right)}=\frac{3x}{\left(x-2\right)\left(5-x\right)}\)
Vì \(\left(x-2\right)\left(5-x\right)\ne0\)
\(\Rightarrow-2x^2+10x=0\Rightarrow-2x\left(x-5\right)=0\Rightarrow\orbr{\begin{cases}x=0\\x=5\end{cases}}\)
e)\(\left(x^2+2x\right)^2+9x^2+18x+20=0\Leftrightarrow x^4+4x^3+13x^2+18x+20=0\)
đến đó mk ko nghĩ ra cách làm mong bạn thông cảm ^.^
e)
