Tìm số tự nhiên n , biết rằng :
a) 1+2+3+4+...+n=231
b) 1+3+5+7+...+(2n-1)=169
a,2/5+3/7+-3/5
b,1-5/7:x=-1/3
c,4/5*(x-1/3)=15/8
d,2/3:(2x+1/8)=7/3
e,2x+3/4=10/3-5/4
giúp mình với
Tìm x:
a, -1/3. (15x-9)+ 2/7. (-x-34)= 1- 3/4. (-16x+4)
b, -1/3. (x-5)+ 1/2. (2x-1/3) = -4.(x+1/2) -7
c, 3.(-2x+7) -6. (1/2x) =1.(x-3)
tìm x biết:
(3x-1) [- 1/2x+5]=0
1/4+1/3:(2x-1)=-5
[2x+3/5]2 - 9/25=0
-5(x+1/5)-1/2(x-2/3)=3/2x - 5 /6
[x+1/2]x [2/3-2x]=0
17/2-|2x-3/4|=-7/4
2/3x-1/2x =5/12
(x+1/5)2+17/25=26/25
[x.44/7+3/7].11/5-3/7=-2
3[3x-1/2]+1/9=0
a,x - 1/2 - (-1/6)
b,x + 5/6 = 3/8
c,2/3 . x -1/2 = 5/6
d, x/7 = 6/-21
e,(7/3 x -0,6) : 3^2/5 = 1
f,x/45 = 5/6 + -29/30
g,(4,5 - 2x) . (-1^4/7) =11/14
h,-2/7 + 4/7x=5/7
Tìm x:
Bài 3:
a) 1/3 + 2/3 : x = -7
b) 3 1/2 - 1/2 x = 2/3
c) [(x + 1/3) * 3/4 +5] : 2=3
d) (1 2/3 - x). 0,75 - 2 = 1/2
e) x + 75% x = -1,6
f) (x - 2/3) (2x+1) = 0
g) 1 - (2x + 1/2) 2 = 3/4
h) 5/1.6 + 5/6.11 + ... + 5/(5x + 1).(5x + 6) = 2020/2021
Giúp mình bài 3 với, ai làm được đúng hết mình sẽ tik hết nhé! Hurry up!
Tìm x
a) ( 2x -1)+3/15= 3/2
b) x+ 46/15= 1,5
c) ( -2x +1) + 3/15= 5/3
d) -13/3 -2x -1= 0,6
e) 3x -1/2x = 7/2-3
f) x÷5=6÷7
g) 2x-1/3 = 16/3
Tìm x biet:
a,5/2x+x=32/15
b,x-7/2x=-32/15
c,-7/3x-7/4x+11/3=18/5
d,-5/6-3x=2/3
e,2x-5/9=-2/3
f,1/2-2/3x=7/12
g,7-|2x-3|=4
h,(19x+2.5^2):14=(13-8)^2-4^2
i,3/4x-2/3=2/7.1/6+5/7.1/6
k,(x+1/2).(2/3-2x)=0
l,x/2013-1/10-1/15-1/21-........-1/120=5/8
Bài 1:
a)-2x-3.( x-17 )= 34-2.( -x+25 )
b)17x+3.( -16x-37 )= 2x+43-4x
c){-3x+2. [ 45-x-3 ( 3x+7 ) -2x]+4x} = 55
g)-103-57: [ 5.( 2x-1 )2-( -9 )0 ]
Bài 2:
a)-5.( -x+7 )-3.( -x-5 )=-4.( 12-x )+48
b)7.( -x-7 )-4.( -2x-11 )=7.( 4x+10 )+9
c)-2.( 15-3x )-4.( -7x+8 )=-5-9.( -2x+1 )
d)5.( -3x-7 )-4.( -2x-11 )=7.( 4x+10 )+9
e)4( x-2 )2-13=( -3 )2.2-11.( -3 )
f)-52-( 2x-1 )3=( -13 ).( -3 )