`4x^2-25=0`
`4x^2=0+25`
`4x^2=25`
`x^2=25:4`
`x^2=25/4`
\(x^2=\left(\pm\dfrac{5}{2}\right)^2\)
Vậy `x = {-5/2 ; 5/2}`
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Tìm x
a.4x^2-25=0
b(x-1).(4x^2-49)=0
Tìm x,biết:
a)4x-(3+5x)=14
b)x2-4x=0
c)(x-3)2=4/25
Bài 1: Tìm x biết :
a) (x+2)^2 - (3x-7)^2=0
b) (4x+1) -(5x-3)^2=0
c) 25(x-3)^2 - 49(2x+1)^2=0
d) 9(3x-2)^2=121(1-4x)^2
e) (x-5/4)^2=(5x+1/2)^2
1) 2( 3x + 5) - 6=0
2) 5x + 3 ( 4+ 2x ) = 25
3) 3 ( 4x + 1) +2 (x - 1) =105
4) 30- [ 2( x - 3 ) - 2 ] = 14
5) 3 ( x - 8 ) (4x + 5 ) - 8 ( x - 8 ) = 0
6) 4x = 8
Các bạn giúp mik với :(
a,-(4x-25)+(214+2x)=-x+213
b,(x+2).(x-7)=0
c,x³-2x²=0
a.(x-2) . (y + 1) = 5
b.xy + 4x -2y = 25
c.(x-1) . (y+2) > 0
d.(x+3) . (y-5) < 0
Tìm x:
a, 2x3 - 32x = 0
b, ( 3x - 2 )2 - (x + 5 )2 = 0
c, 2( x+3 ) - x2 - 3x = 0
d, 4x2 - 25 - ( 2x + 5 )( x + 7) = 0
Tìm x:
a) 3/4x + 2/5x=1
b) ( x-9/11)( x-25/31)=0
c) x-3/7:9/14=7/3
Ai giúp đc k ah?!
B) 17X - ( -16X - 37 ) + 2x + 43
C) -2x -3.( x-17) = 34 -2 (-2x +25)
D) 17x+ 3. ( -16x -37) = 2x +43 -4x
E) {- 3x +2. [45 - x-3 (3x + 7) - 2x] + 4x} =55
F) -103 - 57 : [ -2 ( 2x -1 )2 - ( -9 )0 ] - 106
G) -2x + 3. { 12-2 [ 3x - ( 20 + 2x ) - 4x ] + 1} = 45
3(x+2)-5(x-1)=-x+10
-4(2x-1)-3(x+2)=-20
-2(3x+2)-2(4x-1)=26
(x+2)2=4
(x-3)2=25
-3(x+2)=0
4(x-1)=0