a) 280 – ( x – 140 ) : 35 = 270 b) ( 190 – 2x ) : 35 – 32 = 16 c) 720 : [ 41 – ( 2x – 5 ) ] = 23 .5d) ( x : 23 + 45 ) . 37 – 22 = 24 . 105 e) ( 3x – 4 ) . ( x – 1 ) 3 = 0 ; f) 22x-1 : 4 = 83 g) x17 = x h) ( x – 5 ) 4 = ( x – 5 ) 6 i) ( x + 2 ) 5 = 210 k ) 1 + 2 + 3 + … + x = 78 l) ( 3 .x – 24) . 73 = 2 .74 n) 5x : 52 = 125 m) ( x + 1) 2 = ( x + 1) 0 ; o) ( 2 + x ) + ( 4 + x ) + ( 6 + x ) + ……+...
Đọc tiếp
a) 280 – ( x – 140 ) : 35 = 270
b) ( 190 – 2x ) : 35 – 32 = 16
c) 720 : [ 41 – ( 2x – 5 ) ] = 23 .5
d) ( x : 23 + 45 ) . 37 – 22 = 24 . 105
e) ( 3x – 4 ) . ( x – 1 ) 3 = 0 ; f) 22x-1 : 4 = 83
g) x17 = x
h) ( x – 5 ) 4 = ( x – 5 ) 6
i) ( x + 2 ) 5 = 210
k ) 1 + 2 + 3 + … + x = 78
l) ( 3 .x – 24) . 73 = 2 .74
n) 5x : 52 = 125
m) ( x + 1) 2 = ( x + 1) 0 ;
o) ( 2 + x ) + ( 4 + x ) + ( 6 + x ) + ……+ ( 52 + x ) = 780
p) 70 
x , 80 x vµ x > 8
q) x 12 , x 25 , x 30 vµ 0 < x < 500
nhớ giúp nhaaaaa
a) 280 – ( x – 140 ) : 35 = 270
=> ( x - 140 ) : 35 = 280 - 270 = 10
=> x - 140 = 10 x 35 = 350
=> x = 350 + 140 = 490
b) ( 190 – 2x ) : 35 – 32 = 16
=> ( 190 - 2x ) : 35 = 16 + 32 = 48
=> 190 - 2x = 48 x 35 = 1680
=> 2x = 190 - 1680 = -1490
=> x = -1490 : 2 = -745