1) a) 4x-10=0
4x=10
=>x=2,5
b) 7-3x=9-x
7-3x=-(3x-7)
-2x=2
=>x=-1
c) 2x-(3-5x)=4(x+3)
7x-3=4(x+3)
7x-3=4x+12
=>3x=15
=>x=5
d) 2x+3/3=5-4x/2
=>(2x+3)2=3(5-4x)
=>x=19/6
Bài 1 :
a)
\(4x-10=0\\ \Leftrightarrow4x=10\\ \Leftrightarrow x=\dfrac{5}{2}\)
b)
\(7-3x=9-x\\ \Leftrightarrow2x=-2\\ \Leftrightarrow x=-1\)
c)
\(2x-\left(3-5x\right)=4\cdot\left(x+3\right)\\ \Leftrightarrow2x-3+5x=4x+12\\ \Leftrightarrow3x=15\\ \Leftrightarrow x=5\)
d)
\(\dfrac{2x+3}{3}=\dfrac{5-4x}{2}\\ \Leftrightarrow4x+6=15-12x\\ \Leftrightarrow16x=9\\ \Leftrightarrow x=\dfrac{9}{16}\)
e)
\(x-\dfrac{x+1}{3}=\dfrac{2x+1}{5}\\ \Leftrightarrow\dfrac{2x-1}{3}=\dfrac{2x+1}{5}\\ \Leftrightarrow10x-5=6x+3\\ \Leftrightarrow4x=8\\ \Leftrightarrow x=2\)
f)
\(\dfrac{x-4}{5}+\dfrac{3x-2}{10}-x=\dfrac{2x-5}{3}-\dfrac{7x+2}{6}\\ \Leftrightarrow10x-40+15x-10-50x=12x-30-\left(21x+6\right)\\ \Leftrightarrow-25x-50=-9x-36\\ =\Leftrightarrow16x=14\\ \Leftrightarrow x=\dfrac{7}{8}\)
Bài 2:
a: =>x+2=0 hoặc 3-x=0
=>x=3 hoặc x=-2
b: =>(x-3)(x+3)(3x+5)=0
=>\(x\in\left\{3;-3;-\dfrac{5}{3}\right\}\)
c: =>(5x+3)(x-1)=0
=>x=1 hoặc x=-3/5
d: =>(x+6)(3x-1+1)=0
=>3x(x+6)=0
=>x=0 hoặc x=-6
e: =>(1-x)(5x+3)-(3x-7)(x-1)=0
=>(1-x)(5x+3+3x-7)=0
=>(1-x)(8x-4)=0
=>x=1/2 hoặc x=1
f: =>(x-9)(x+2)=0
=>x=9 hoặc x=-2
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