tìm x : ( x + 1) + ( x + 2 ) + ( x + 3 ) + ( x + 4 ) + ( x + 5 ) + ( x + 6 ) = 71
bài 2: Tìm\(x\in N\)biết:
1) 71 x 2 - 6 x ( 2 x X + 5 ) = 105 : 103
2) 53 x ( 3 x X + 2 ) : 13 = 103 : (135 : 134)
3) (X -1)x+7 - (X-1)x+1
4) ( x - 3 )x+2 = ( x -3 )x+6
Giúp em với
bài 2: Tìm x ∈ N biết:
1) 71 x 2 - 6 x ( 2 x X + 5 ) = 105 : 103
2) 53 x ( 3 x X + 2 ) : 13 = 103 : (135 : 134)
3) (X -1)x+7 - (X-1)x+1
4) ( x - 3 )x+2 = ( x -3 )x+6
Giúp em với
3 phần trên đễ quá mik ko làm mik chỉ làm phàn 4 thôi nhé
4) ta có: (x-3)^x+2=(x-3)^x+6
=>(x-3)^x*(x-3)^2=(x-3)^x*(x-3)^6
=>(x-3)^x=(x-3)^x*(x-3)^4
=>(x-3)^x*(x-3)^4-(x-3)^x*1=0
=>(x-3)^x*((x-3)^4-1)=0
=>(x-3)^x=0 hoặc (x-3)^4-1=0
còn lại cậu tự làm nha nó đẽ mà
1)71.2-6(2.x+5)=105:103
71.2-6(2.x+5)=102
6(2.x+5)=142-100
6(2.x+5)=42
2.x+5 =42:6
2x+5 =7
2x =7-5
2x =2
x =1
2)53.(3.x+2):13=103:(135:134)
53.(3x+2):13 =103:13
53(3x+2) =103
125(3x+2) =1000
3x+5 =1000:125
3x+5 =8
3x =8-5
3x =3
x =3:3
x =1
Tính nhanh :
1/2 x 17/5 x 1/6 + 1/3 x 71/5 x 1/4 - 1/12 x 28/5
Bài 3: Tìm x e Z:
1) 71 – (33 + x)= 26
2) (x + 73) – 26 = 76
3) x - 7 = -5
4) -23 +x = - (- 25)
5) -5 < x ≤ 6
6) 140 : (x – 8) = 7
1, <=>33+x=45
<=> x = 12
Vậy x=12
2, <=>x+73 =102
<=> x =29
3,x=2
4, -23+x=25<=>x=2
6, x-8=20<=>x=28
Tìm các số nguyên x, y sao cho:
a, 5/x - y/3 =1/6
b, 5x - 2y + xy = 71
c, xy + 3x - 7y = 21
d, 2xy - 6y + x = 9
e, x/3 - 4/y = 1/5
g, 4/x + y/3 = 5/6
Tìm x
1. 71- ( 33 + x ) = 26
2. 3636 : ( 12. x - 91 ) =36
3. ( x- 15 ) - 218 = 0
4. 45+ ( x- 6 ) . 3 =81
5. 124. x - 4. x - 70. x= 150
6. ( x+ 70 ) . a= aaaa ( 0 < a < 9, a E N )
\(71-\left(33+x\right)=26\)
<=> \(71-33-x=26\)
<=> \(38-x=26\)
<=> \(x=38-26=12\)
\(3636:\left(12x-91\right)=36\)
<=> \(12x-91=101\)
<=> \(12x=192\)
<=> \(x=16\)
\(\left(x-15\right)-218=0\)
<=> \(x-15=218\)
<=> \(x=233\)
\(45+\left(x-6\right).3=81\)
<=> \(\left(x-6\right).3=36\)
<=> \(x-6=12\)
<=> \(x=18\)
\(124x-4x-70x=150\)
<=> \(\left(124-4-70\right).x=150\)
<=> \(50x=150\)
<=> \(x=3\)
1) 71 - ( 33 + x ) = 26
<=> 33 + x = 71 - 26
<=> 33 + x = 45
<=> x = 12
2) 3636 : ( 12x - 91 ) = 36
<=> 12x - 91 = 101
<=> 12x = 192
<=> x = 16
3) ( x - 15 ) - 218 = 0
<=> x - 15 = 218
<=> x = 218 + 15
<=> x = 233
4) 45 + ( x - 6 ) .3 = 81
<=> 45 + ( x - 6 ) = 27
<=> x - 6 = -18
<=> x = -12
5) 124x - 4x - 70x = 150
<=> 5x = 150
<=> x = 150 : 50
<=> x = 3
Bài 1: Tìm x
a) 51 + ( 20 - 3 . x ) : 5 = 55
b) 71 + ( 26 - 3 . x ) : 5 = 75
c ) ( x - 6 ) \(^2\)= 25
d ) ( x - 6 )\(^3\)= ( x - 6 ) \(^2\)
(20-3.x):5=55-51
(20-3.x):5=4
20-3.x=4.5
20-3.x=20
3.x=20-20
3.x=0
x=0:3
x=0
không đc đừng ném mik nha
9 - 3 x ( X - 9 ) = 6
4 + 6 x ( X + 1 ) 70
\(\dfrac{X}{13}+\dfrac{15}{26}=\dfrac{46}{52}\)
\(\dfrac{11}{14}-\dfrac{3}{X}=\dfrac{5}{14}\)
5 x ( 3 + 7 x X ) = 40
X x 6 + 12 : 3 = 120
X x 3,7 + X x 6,3 = 120
( 15 x 24 - X ) : 0,25 = 100 : \(\dfrac{1}{4}\)
71 + 65 x 4 = \(\dfrac{X+140}{X}\)+ 260
( X +1 ) + ( X + 4 ) + ( x + 7 ) + ...... + (X + 28 ) = 155
đây là bài tìm X
Giải:
\(9-3\times\left(x-9\right)=6\)
\(3\times\left(x-9\right)=9-6\)
\(3\times\left(x-9\right)=3\)
\(x-9=3:3\)
\(x-9=1\)
\(x=1+9\)
\(x=10\)
\(4+6\times\left(x+1\right)=70\)
\(6\times\left(x+1\right)=70-4\)
\(6\times\left(x+1\right)=66\)
\(x+1=66:6\)
\(x+1=11\)
\(x=11-1\)
\(x=10\)
\(\dfrac{x}{13}+\dfrac{15}{26}=\dfrac{46}{52}\)
\(\dfrac{x}{13}=\dfrac{23}{26}-\dfrac{15}{26}\)
\(\dfrac{x}{13}=\dfrac{4}{13}\)
\(\Rightarrow x=4\)
\(\dfrac{11}{14}-\dfrac{3}{x}=\dfrac{5}{14}\)
\(\dfrac{3}{x}=\dfrac{11}{14}-\dfrac{5}{14}\)
\(\dfrac{3}{x}=\dfrac{3}{7}\)
\(\Rightarrow x=7\)
\(5\times\left(3+7\times x\right)=40\)
\(3+7\times x=40:5\)
\(3+7\times x=8\)
\(7\times x=8-3\)
\(7\times x=5\)
\(x=5:7\)
\(x=\dfrac{5}{7}\)
\(x\times6+12:3=120\)
\(x\times6+4=120\)
\(x\times6=120-4\)
\(x\times6=116\)
\(x=116:6\)
\(x=\dfrac{58}{3}\)
\(x\times3,7+x\times6,3=120\)
\(x\times\left(3,7+6,3\right)=120\)
\(x\times10=120\)
\(x=120:10\)
\(x=12\)
\(\left(15\times24-x\right):0,25=100:\dfrac{1}{4}\)
\(\left(360-x\right):0,25=400\)
\(360-x=400.0,25\)
\(360-x=100\)
\(x=360-100\)
\(x=260\)
\(71+65\times4=\dfrac{x+140}{x}+260\)
\(\left(x+140\right):x+260=71+260\)
\(x:x+140:x+260=331\)
\(1+140:x+260=331\)
\(140:x=331-1-260\)
\(140:x=70\)
\(x=140:70\)
\(x=2\)
\(\left(x+1\right)+\left(x+4\right)+\left(x+7\right)+...+\left(x+28\right)=155\)
\(10\times x+\left(1+4+7+...+28\right)=155\)
Số số hạng \(\left(1+4+7+...+28\right)\) :
\(\left(28-1\right):3+1=10\)
Tổng dãy \(\left(1+4+7+...+28\right)\) :
\(\left(1+28\right).10:2=145\)
\(\Rightarrow10\times x+145=155\)
\(10\times x=155-145\)
\(10\times x=10\)
\(x=10:10\)
\(x=1\)
Đều theo cách lớp 5 nha em!
Tích sau có tận cùng bằng bao nhiêu số 0.
a, 5 x 6 x 7 x..........x 60 x 61.
b, 12 x 13 x14 x......x 80 x 81.
c, 1 x 2 x 3 x......x 70 x 71.
d, 3 x 4 x 5 x.........x 100 x 101.
Giúp mình với!