2x + 12 = 3 . ( x - 7 )
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\(d,=24x^2-38x+3\\ e,=x^2-12x+35\\ f,=\left(x^2-144\right)\left(4x-1\right)=4x^3-x^2-576x+144\)
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Gọi a,b,c,... cho dễ nhé!
a,\(7+2x=22-3x\)
\(\Leftrightarrow2x+3x=22-7\)
\(\Leftrightarrow5x=15\)
\(\Leftrightarrow x=3\)
Vậy...
b,\(x-12+4x=25+2x-1\)
\(\Leftrightarrow x+4x-2x=25-1+12\)
\(\Leftrightarrow3x=36\)
\(\Leftrightarrow x=12\)
Vậy...
c,\(7-\left(2x+4\right)=-\left(x+4\right)\)
\(\Leftrightarrow7-2x-4=-x-4\)
\(\Leftrightarrow-2x+x=-4+4-7\)
\(\Leftrightarrow-x=-7\)
\(\Leftrightarrow x=7\)
Vậy...
d,\(8x-3=5x+12\)
\(\Leftrightarrow8x-5x=12+3\)
\(\Leftrightarrow3x=15\)
\(\Leftrightarrow x=5\)
Vậy...
e,\(x+2x+3x-19=3x+5\)
\(\Leftrightarrow x+2x+3x-3x=5+19\)
\(\Leftrightarrow3x=24\)
\(\Leftrightarrow x=8\)
Vậy...
f,\(\left(x-1\right)-\left(2x-1\right)=9-x\)
\(\Leftrightarrow x-1-2x+1=9-x\)
\(\Leftrightarrow x-2x+x=9-1+1\)
\(\Leftrightarrow0x=9\) (Vô lý)
Vậy...
a, \(7+2x=22-3x\)
\(\Rightarrow7+2x-22+3x=0\)
\(\Rightarrow5x-15=0\)
\(\Rightarrow5x=15\Rightarrow x=3\)
b, \(x-12+4x=25+2x-1\)
\(\Rightarrow3x-12-24-2x=0\)
\(\Rightarrow x-36=0\Rightarrow x=36\)
c, \(7-\left(2x+4\right)=-\left(x+4\right)\)
\(\Rightarrow7-2x-4=-x-4\)
\(\Rightarrow3-2x+x+4=0\)
\(\Rightarrow-x=-7\Rightarrow x=7\)
d, \(8x-3=5x+12\)
\(\Rightarrow8x-3-5x-12=0\)
\(\Rightarrow3x-15=0\)
\(\Rightarrow3x=15\Rightarrow x=5\)
e, \(x+2x+3x-19=3x+5\)
\(\Rightarrow6x-19-3x-5=0\)
\(\Rightarrow3x-24=0\)
\(\Rightarrow3x=24\Rightarrow x=8\)
f, \(\left(x-1\right)-\left(2x-1\right)=9-x\)
\(\Rightarrow x-1-2x+1-9+x=0\)
(hình như câu này bị sai đề rồi, bạn xem lại đề nhé)
Chúc bạn học tốt!
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\(a,-5.\left(-x+7\right)-3.\left(-x-5\right)=-4.\left(12-x\right)+48\)
\(5x-35-3x+15=-48+4x+48\)
\(2x-10=4x\)
\(2x-4x=10\)
\(-2x=10\)
\(x=-5\)
\(b,\left(-x-7\right)-5.\left(-x-3\right)=12.\left(3-x\right)\)
\(-x-7+5x+15=36-12x\)
\(4x+8=36-12x\)
\(4x+12x=36-8\)
\(16x=28\)
\(x=1,75\)
các câu còn lại tương tự nha
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a) 3x - 4 (2x-7) = 3x - 3
3x - 8x + 28 = 3x - 3
=> 3x - 8x - 3x = -3 -28
-8x = -31
x = 31/8
b) 3(2x-7) - (4-2x) = 2x -1
6x - 7 - 4 + 2x = 2x -1
=> 6x + 2x - 2x = -1 + 7+4
6x = 10
x = 5/3
c) (x-2).(2x+12)=0
=> x -2 = 0 => x = 2
2x + 12 = 0 => 2x = -12 => x = -6
KL: x = 2 hoặc x = -6
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a ) \(-5\times\left(-x+7\right)-3\times\left(-x-5\right)=-4\times\left(12-x\right)+48\)
\(\Leftrightarrow5x-35+3x+15=-48+4x+48\)
\(\Leftrightarrow5x-3x+4x=35-15-48+48\)
\(\Leftrightarrow2x=20\)
\(\Leftrightarrow x=10\)
b ) \(-2\times\left(15-3x\right)-4\times\left(-7x+8\right)=-5-9\times\left(-2x+1\right)\)
\(\Leftrightarrow-30+6x-28x-32=-5+18x-9\)
\(\Leftrightarrow6x-28x-18x=30+32-5-9\)
\(\Leftrightarrow-40x=48\)
\(\Leftrightarrow x=-1.2\)
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2x + 12 = 3 . (x - 7)
2x + 12 = 3x - 21
2x + 12 + 21 = 3x
2x + 33 = 3x
=) x = 33