Tìm x biết | 5x - 2/3 | = 2/3 - 5x
Tìm x biết a) (x^2-4x+5)_(x^2-2x+1)=3 lớp 7
b)(4x^3-5X^2+3x-1)+(3-5x+5x^2-4x^3)=2
c)(3x-2)-(5x+4)=(x-3)-(X+5)
a, \(-4x+5+2x-1=3\Leftrightarrow-2x=-1\Leftrightarrow x=\dfrac{1}{2}\)
b, \(-2x+2=2\Leftrightarrow x=0\)
c, \(-2x-6=-8\Leftrightarrow x=1\)
tìm x biết
(5x+1)^2 - (5x+3).(5x-3)=30
(x+3).(x^2-3x+9)-x.(x-2).(x+2)=15
1 , <=> 25x^2 + 10x + 1 - ( 25x^2 - 9) = 30
<=> 25x^2 + 10x + 1 - 25x^2 + 9 = 30
<=> 10x + 10 = 30
<=> 10 ( x + 1) = 30
<=> x + 1 = 3
<=> x = 2
2, ( x + 3)(x^2 - 3x + 9 ) - x(x+2)(x-2) = 15
<=> x^3 - 27 - x(x^2 - 4) = 15
<=> x^3 - 27 - x^3 + 4x = 15
<=> 4x -27 = 15
<=> 4x = 15 + 27
<=> 4x =42
<=> x = 42/4 = 21/2
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tìm x biết: (5x+1)^2-(5x+3)(5x-3)=30
\(\left(5x+1\right)^2-\left(5x+3\right)\left(5x-3\right)=30\)
\(25x^2+10x+1-\left(25x^2-9\right)=30\)
\(25x^2+10x+1-25x^2+9=30\)
\(10x+10=30\)
\(10x=20\)
\(x=2\)
(5x+1)2-(5x+3)(5x-3)=30
=>25x2+10x+1-25x2+9=30
=>(25x2-25x2)+10x+1+9=30
=>10x+10=30
=>10x=20
=>x=2
Tìm x biết (x^2-1)^3+(5x+7)^3=(x^2+5x-6)^3
tìm x biết
a) 5x(2x-7)+2x(8-5x)=5
b)(3x-5)(7-5x)-(5x+2)(2-3x)=4
c)5(2x-3)^2-5(x+1)^2-15(x+4)(x-4)=-10
d) 5x(x-3)(x+3)-(2x-3)^2 -5(x+2)^3+34x(x+2)=1
a)
<=> 10x - 35 + 16x - 10 = 5
<=> 10x + 16x = 5 + 35 + 10
<=> 26x = 50
<=> x = 50/26 = 25/13
Tìm x, biết:
5 x - 3 4 x - 2 [ 4 x - 3 ( 5 x - 2 ) ] = 182 .
Thực hiện phá ngoặc lần lượt và rút gọn VT = -73x + 36.
Giải phương trình -73x + 36 = 182 thu được x = -2.
TÌM X biết:
a. (5x - 2)(5x + 2) - (5x + 3)(5x - 4) = 8
b. (4x - 3)( 4x + 2) + (4x + 5)(1 - 4x) =2.52
a) \(\left(5x-2\right)\left(5x+2\right)-\left(5x+3\right)\left(5x-4\right)=0\)
\(\Leftrightarrow5x+8=8\)
\(\Leftrightarrow5x=8-8\)
\(\Leftrightarrow x=5.0\)
\(\Leftrightarrow x=0\)
b)
\(\left(4x-3\right)\left(4x+2\right)+\left(4x+5\right)\left(1-4x\right)=2.5^2\)
\(16x^2+8x-12x-6+4x-16x^2+5-20x=50\)
\(-20x-1=50\)
\(-20x=51\)
\(x=\frac{-51}{20}\)
Vậy \(x=\frac{-51}{20}\)
tìm x ,biết
a, x^2 -4x =12
b, ( 5x+1)^2 - (5x -3)(5x+3)=30
c, (x-1) ( x^2 +x +1 ) + x(x +2) (2-x)=5
d, 5x(x-3)^2 -5 (x-1)^3 +15 (x+4) (x-4) =5
Tìm x biết :
5x-3{4x-2[4x-3(5x-2)]}=182
5x-3{4x-2[4x-3(5x-2)]}
= 5x - 3.[4x - 2(4x - 15x + 6)]
= 5x - 3.(4x - 8x + 30x - 12)
= 5x - 12x + 24x - 90x + 36
= -73x + 36 = 182
=> -73x = 182 - 36 = 146
=> x = 146 : (-73) = -2
\(VT=-\left(73x-36\right)\)
\(\Leftrightarrow-\left(73x-36\right)=182\)
\(\Leftrightarrow36-73x=182\)
\(\Leftrightarrow-73x=182-36\)
\(\Leftrightarrow-73x=146\)
\(\Leftrightarrow x=-2\)
5x -3 { 4x - 2 [ 4x - 3 (5x - 2)]} = 182
<=> 5x -3 { 4x -2 [ 4x - 15x +6 ]} =182
<=> 5x -3 { 4x -2 [ -11x +6 ]} =182
<=> 5x -3 { 4x + 22x -12 } = 182
<=> 5x -3 { 26x -12 } =182
<=> 5x - 78x + 36 = 182
<=> -73x = 146
<=> x= -2