tìm số tự nhiên x, biết:
a) 21 - 4x = 13
b) 30 : (x - 3) + 1 = \(4^5\) : \(4^3\)
c) (x - 1)\(^3\) + 5 . 6 = 38
bài 9 :
6 mũ 2 x 73 + 36 x 3 mũ 3
197 -[ 6 x ( 5 - 1) mũ 2 +2022 mũ 0 ] : 5
bài 10: tìm số tự nhiên biết x
21- 4 . x = 13
30 : ( x - 3 ) + 1 = 4 mũ 5 : 4 mũ 3
( x - 1 ) mũ 3 + 5 . 6 = 38
Bài 9,
62x73+36x33=36x73+36x27=36(73+27)=36x100=3600.
197-\([\)6x(5-1)2+20220\(]\):5=197-\([\)6x16+1\(]\):5=197-97:5=197-97/5=888/5.
Bài 10,
21-4x=13
=>4x=21-13=8
=>x=8:4=2.
30:(x-3)+1=45:43=42=16
=>30:(x-3)=16-1=15
=>x-3=30:15=2
=>x=2+3=5.
(x-1)3+5x6=38
=>(x-1)3+30=38
=>(x-1)3=38-30=8=23
=>x-1=2
=>x=3.
Mình chỉ cần kết quả thui ạ, thanks mn!
Tìm các cặp số tự nhiên (x, y) biết:
a) ( x – 3)(y + 5) = 13
b) (8 - 2x)( 11 – 5y)
c) ( 3x – 1)( y + 2) = 16
d) x – 3 = y(x – 1)
Bài 12: Tính :
a) A = 1 + (-3) + 5 + ( - 7) +….+ 17 + ( -19);
b) B = (- 2) + 4 + (-6) + 8 + …+ ( - 18) + 20;
c) C = 1 + (-2) + 3 + (-4) + ….+ 1999 + ( - 2000) + 2001;
Bài 13: Tìm số nguyên x, biết:
a) –x + 20 = -(-15) –(+8) + 13
b) –(-10) + x = -13 + (-9) + (-6)
Bài 13:
a: =>20-x=15-8+13=20
hay x=0
tìm \(x\) là số tự nhiên biết:
a)\(\dfrac{2}{3}+\dfrac{3}{4}< x< 1\dfrac{1}{3}+\dfrac{4}{5}\) b)\(\dfrac{5}{6}-\dfrac{1}{4}< x< 2\dfrac{1}{3}-\dfrac{2}{5}\)
Tìm số tự nhiên x, biết:
a, 128 – 3( x + 4 ) = 23
b, [( 4x + 28 ).3 + 55] : 5 = 35
a) \(128-3\left(x+4\right)=23\)
\(\Rightarrow3\left(x+4\right)=128-23\)
\(\Rightarrow3\left(x+4\right)=105\)
\(\Rightarrow x+4=35\)
\(\Rightarrow x=35-4\)
\(\Rightarrow x=31\)
b) \(\left[\left(4x+28\right)\cdot3+55\right]:5=35\)
\(\Rightarrow\left(4x+28\right)\cdot3+55=35\cdot5\)
\(\Rightarrow\left(4x+28\right)\cdot3+55=175\)
\(\Rightarrow\left(4x+28\right)\cdot3=120\)
\(\Rightarrow4x+28=40\)
\(\Rightarrow4x=12\)
\(\Rightarrow x=3\)
a, \(128-3\left(x+4\right)=23\)
\(=>3\left(x+4\right)=128-23\)
\(=>3\left(x+4\right)=105\)
\(=>x+4=105:3\)
\(=>x+4=35\)
\(=>x=35-4\)
\(=>x=31\)
b, \(\left[\left(4x+28\right).3+55\right]:5=35\)
\(=>\left(4x+28\right).3+55=35.5\)
\(=>\left(4x+28\right).3+55=175\)
\(=>\left(4x+28\right).3=175-55\)
\(=>\left(4x+28\right).3=120\)
\(=>4x+28=120:3\)
\(=>4x+28=40\)
\(=>4x=40-28\)
\(=>4x=12\)
\(=>x=12:4\)
\(=>x=3\)
\(#WendyDang\)
a) 128 - 3 (x + 4) =23
3.( x + 4) = 128 -23
3. ( x + 4) = 105
x + 4 = 105 :3
x + 4 = 35
x = 35 -4
x = 31
Bài 2: Tìm x, biết:
a) 75 - (x + 11) = 13
b) 29 + (x + 11) = 57
c) 11 + x : 5 = 13
d) 13 + 2(x + 1) = 15
e) 2x + 21 = 41
f) 12 + 3(x – 2) = 60
g) 24x – 11.13 = 11.11
h) 17 – (x – 4) : 2 = 3
c: Ta có: 11+x:5=13
\(\Leftrightarrow x:5=2\)
hay x=10
d: Ta có: \(13+2\left(x+1\right)=15\)
\(\Leftrightarrow2x+2=2\)
\(\Leftrightarrow2x=0\)
hay x=0
e: Ta có: 2x+21=41
\(\Leftrightarrow2x=20\)
hay x=10
f: Ta có: \(12+3\left(x-2\right)=60\)
\(\Leftrightarrow3\left(x-2\right)=48\)
\(\Leftrightarrow x-2=16\)
hay x=18
g: Ta có: \(24x-11\cdot13=11\cdot11\)
\(\Leftrightarrow24x=11\cdot24\)
hay x=11
h: Ta có: \(17-\left(x-4\right):2=3\)
\(\Leftrightarrow\left(x-4\right):2=14\)
\(\Leftrightarrow x-4=28\)
hay x=32
Tìm \(x\) là số tự nhiên biết:
a)\(\dfrac{2}{3}+\dfrac{3}{4}< x< 1\dfrac{1}{3}+\dfrac{4}{5}\) b)\(\dfrac{5}{6}-\dfrac{1}{4}< x< 2\dfrac{1}{3}-\dfrac{2}{5}\)
mn giúp mik vs mik cần gấp
`a, 2/3 +3/4 = (8+9)/12=17/12.`
`1 1/3+4/5 = 4/3 + 4/5 = (20+12)/15=32/15`.
`=> x=2.`
`b, 5/6-1/4=(20-6)/24=7/12`.
`2 1/3-2/5= 7/3-2/5 = (35-6)/15=29/15`.
`=> x=1`.
a) \(\dfrac{2}{3}+\dfrac{3}{4}=\dfrac{8+9}{12}=\dfrac{17}{12}\)
-> 1 1/3 + 4/5 = 4/3 + 4/5 = 20+12/15 = 32/15
vậy x có thể = 14/14 = 1 (x thuộc N)
Bài 2: Tìm số tự nhiên x, biết:
a) 100-7(x-5)=58 b) 12(x-1):3=43+23
c) 24+5x=75:73 d)5.(x-1)-206=24.4
e) 5(x-4)2-7=13 f) (x+1)+(x+2)+....+(x+30)=795
g) 2x+3 - 3.2x+1=32 h) 221-(3x+2)3=96
Mn bày e gấp
a: Ta có: \(100-7\left(x-5\right)=58\)
\(\Leftrightarrow7\left(x-5\right)=42\)
\(\Leftrightarrow x-5=6\)
hay x=11
b: Ta có: \(12\left(x-1\right):3=4^3+2^3\)
\(\Leftrightarrow12\left(x-1\right)=216\)
\(\Leftrightarrow x-1=18\)
hay x=19
Tìm số tự nhiên x biết:
a) 25 + 7x = 144
b) 33 - 12x = 9
c) 128 - 3(x + 4) = 23
d) 71 + (726 - 3x).5 = 2246
e) 720 : [41 - (2x + 5)] = 40
f) (10 - 4x) + 120 : 8 = 16 + 1
g) x + 9x + 7x + 5x = 2244
h) (x + 1) + (x + 2) + (x + 3) +...+ (x + 100) = 5750
i) 1 + 2 + 3 +...+ x = 500500
j) 51 + 52 + 53 +...+ x = 18825
a: Ta có: \(7x+25=144\)
\(\Leftrightarrow7x=119\)
hay x=17
b: Ta có: \(33-12x=9\)
\(\Leftrightarrow12x=24\)
hay x=2
c: Ta có: \(128-3\left(x+4\right)=23\)
\(\Leftrightarrow3\left(x+4\right)=105\)
\(\Leftrightarrow x+4=35\)
hay x=31
d: Ta có: \(71+\left(726-3x\right)\cdot5=2246\)
\(\Leftrightarrow5\left(726-3x\right)=2175\)
\(\Leftrightarrow726-3x=435\)
\(\Leftrightarrow3x=291\)
hay x=97
e: Ta có: \(720:\left[41-\left(2x+5\right)\right]=40\)
\(\Leftrightarrow41-\left(2x+5\right)=18\)
\(\Leftrightarrow2x+5=23\)
\(\Leftrightarrow2x=18\)
hay x=9
f: Ta có: \(10-4x+120:8=16+1\)
\(\Leftrightarrow4x=17-25=-8\)
hay x=-2
g: Ta có: \(x+9x+7x+5x=2244\)
\(\Leftrightarrow22x=2244\)
hay x=102
h: Ta có: \(\left(x+1\right)+\left(x+2\right)+\left(x+3\right)+...+\left(x+100\right)=5750\)
\(\Leftrightarrow100x+5050=5750\)
\(\Leftrightarrow100x=700\)
hay x=7