Tìm x :
a) x . ( x - 2 ) = 0
b) ( x - 1 ) . ( x - 3 ) = 2
Tính nhanh ( nếu có )
a) 15 . 37 .4 + 120 . 21 + 21 . 5 . 12
b) 19 + 19 . 99 - 25 . 8
c) 27 + 73 - 30 : ( 25 - 10 )
d) 15 - 25 . 8 : ( 25 - 10 )
Tìm x, biết:
a) (x - 3.5).12 = 0;
b) 35. (x - 10) = 35;
c) ( x - 5): 3 + 3 = 24
d) ( x - 4) : 3 - 2 = 100
c) 25.(2.x - 4).12 = 0
d) (x - 4) : 6 - 5 = 10
Tìm x, biết:
a) (x - 3.5).12 = 0; b) 35. (x-10) = 35;
c) ( x -5): 3 + 3 = 24 d) ( x- 4) : 3 - 2 = 100
c) 25.(2.x - 4).12 = 0 d) (x- 4) : 6 - 5 = 10
tìm x,y,z
a) 12/16=-x/4 =21/y-z/80
b) 1/3 . x+2/5.(x-1)=0
c) (2.x-3).(6-2.x)=0
d)-2/3-1/3.(2.x-5)=3/2
e)(3.x-1).(-1/2.x+5)=0
f) (2.x+3/5)^2-9/25=0
1. Tìm x, biết :
a) ( x : 7- 7 ) ( x : 12 - 12 ) = 0 b) 140 - 100 : x = 120
c) 300 - x : 5 = 273 d) 300 - x : 5 = 273
e) ( x : 2 - 2 ) ( x : 3 - 3 ) = 0 f) 58 - x : 18 = 52
g) 214 - 136 : x = 197 h) ( x - 5 ) : 3 = 0
2. Tìm x, biết :
a) ( x - 3.5 ) . 12 = 0 b) 35. ( x - 10 ) = 35
c) ( x - 5 ) : 3 + 3 = 24 d) ( x - 4 ) : 3 - 2 = 100
3. Tìm x, biết :
a) ( x - 5.9 ) . 2 = 0 b) 21. (32 - x ) = 21
c) 25. ( 2. x - 4) . 12 = 0 d) ( x - 4 ) : 6 - 5 = 10
Tìm x biết:a) 29-x/21 + 27-x/23 + 25-x/25 + 23-x/27 + 21-x/29
b)x-10/30 + x-14/43 + x-5/95 + x-148/8 = 0
1.Tìm x , biết :
a)35.(x-10)=35
b)21.(32-x)=21
c)25.(2x.4).12=0
d)(x-4):6-5=10
e)485-(6.x+60)=5
f)315+(135-x)=450
g)346+(210-x)=556
h)(x-32)-68=0
i)274-(9.x+18)=4
j)442+(418-x)=860
k)107+(210-x)=317
l)x-280:35=5.54
m)(x-120):35=5
n)(x+100)=800
o)x.5+10.9=990
p)x-120:30=40
q)(x+120):20=8
r)(x+5).3=300
s)x.2+21:3=27
2.Tính nhanh
a) 99 - 97 + 95 - 93 + 91 - 89 + ... + 7 - 5 + 3 -1
b)47.8 - 27.9 + 47.12 - 27.11
c) 1326 +538-326-62
d) 2391-147-253
e) 8-96+94-92+90-88+...+7-5+3-1
f) 24.42-35.24-24.7
g)42.13-22.5+42.22
h)125:4-25:4
i)1159:125-159:125
*Lưu ý : các dấu (.) bằng với dấu nhân nhé
e) (x + 12 ) . (x - 3) = 0
g) (-x + 5) . (3 - x) = 0
h) ( x - 1 ) . ( x -2 ) - ( -x -3 ) = 0
Bài 3 : tính hợp lý:
a) (15 + 37) + ( 52 - 37 - 17 )
b) ( 38 - 42 +14) - ( 23 - 21 +10)
c) - ( 21 - 32) ) - ( -12 +32 )
d) - ( 12 + 21 - 23) - ( 23 - 21 +10 )
e) ( 57 -752 ) - ( 605 - 53 )
g) ( 55 + 45 + 15) - (15 - 55 +45)
a,|x|-7/6=9/15
b,|x-4/3|=1/6
c,|x-4/3|-1/3=1/2
d,8/3-|7/9-x|=-1/5
e,|x-1/4^2|-25/64=0
f,(x-1/4)^2+17/64=21/32