(x x 2\(\frac{1}{4}\)): 6 + 7 =\(\frac{6}{5}\)- 0,2
tìm x biết
a,\(\left(152\frac{2}{4}-148\frac{3}{8}\right):0,2=x:0,3\)
b,\(\left(85\frac{7}{30}-83\frac{5}{18}\right):2\frac{2}{3}=0,01x:4\)
c,\(\frac{x-1}{x+5}=\frac{6}{7}\)
d,\(\frac{x^2}{6}=\frac{24}{25}\)
e,\(\frac{x-2}{x-1}=\frac{x+4}{x+7}\)
g\(\frac{x-3}{x+5}=\frac{5}{7}\),
a, ( 152 +và 2/4 - 148 và 3/8 ) : 0,2 = x : 0,3
=> 33/8 : 1/5 = x : 3/10
=> x : 3/10 = 165/8
=> x = 99/10
b, ( 85 và 7/30 - 83 và 5/18 ) : 2 và 2/3 = 0,01x : 4
=> 88/45 : 8/3 = 0,01x : 4
=> 0,01x : 4 = 11/15
=> 0,01x = 44/15
=> x = 880/3
c, x - 1/ x + 5 = 6/7
=> 7( x - 1 ) = 6( x + 5 )
=> 7x - 7 = 6x + 30
=> 7x - 6x = 7 + 30
=> x = 37
d, x2/6 = 24/25
=> x2. 25 = 6 . 24
=> x2.25 = 144
=> x2 = 144/25
=> x = ( 12/5)2 hoặc x = ( -12/5)
g, x - 3/ x + 5 = 5/7
=> 7( x - 3 ) = 5 ( x + 5 )
=> 7x - 21 = 5x + 25
=> 7x - 5x = 21 + 25
=> 2x = 46
=> x = 23
1)\(\frac{6}{15}-\frac{7}{8}+3+\frac{3}{5}-\frac{2}{16}\)
2)
\(\hept{1\begin{cases}1\\5\end{cases}-0,2\hept{\begin{cases}\\\\\end{cases}}}.X=1\)
b)
\(\frac{3}{4}.X+\frac{1}{5}.X=\frac{1}{6}\)
1/Tính
a)
\(\frac{2}{5}+\frac{1}{5}\times\left(\frac{3}{4}\right)\)
b)\(\frac{5}{12}\times\left(\frac{-3}{4}\right)+\frac{7}{12}\times\left(\frac{-3}{4}\right)\)
c)\(\frac{2^{15}\times9^4}{6^6\times8^3}\)
2/Tìm x biết:
a)\(\frac{5}{7}+\frac{2}{7}x=1\)
b)0,2+\(\left|x-1,3=1,5\right|\)
c)\(2^x+5=37\)
d)\(2^x+2^{x+1}=48\)
Bài 1:
a) \(\frac{2}{5}+\frac{1}{5}.\left(\frac{3}{4}\right)\)
= \(\frac{2}{5}+\frac{3}{20}\)
= \(\frac{11}{20}\)
b) \(\frac{5}{12}.\left(-\frac{3}{4}\right)\) + \(\frac{7}{12}.\left(-\frac{3}{4}\right)\)
= \(\left(\frac{5}{12}+\frac{7}{12}\right).\left(-\frac{3}{4}\right)\)
= 1.\(\left(-\frac{3}{4}\right)\)
= \(-\frac{3}{4}\)
Còn câu c) đang nghĩ.
Bài 2:
a) \(\frac{5}{7}+\frac{2}{7}\)x = 1
1.x = 1
x = 1 : 1
x = 1
Vậy x = 1.
b) 0,2 + | x - 1, 3 = 1, 5|
0,2 + x = 1, 5 + 1, 3
0,2 + x = 2, 8
x = 2, 8 - 0, 2
x = 2, 6
Vậy x = 2, 6.
c) 2x + 5 = 37
2x = 37 - 5
2x = 32
2x = 25
=> x = 5
Vậy x = 5.
d) 2x + 2x + 1 = 48
2x . 1 + 2x . 21 = 48
2x . ( 1 + 2) = 48
2x . 3 = 48
2x = 48 : 3
2x = 16
2x = 24
=> x = 4
Vậy x = 4.
Chúc bạn học tốt!
làm bước trung gian giùm mình luôn nhé
thanks trước những bạn làm giùm nhé
mình đang cần gấp lắm sáng mai là mình cần ai đang on làm giùm mình nhé
thanks
Thuy Huynh mk làm nốt câu c bạn ấy chưa làm:
c/ \(\frac{2^{15}.9^4}{6^5.8^3}\)
\(=\frac{2^{15}.\left(3^2\right)^4}{\left(3.2\right)^5.\left(2^3\right)^3}\)
\(=\frac{2^{15}.3^8}{3^5.2^5.2^9}\)
\(=\frac{2^{15}.3^8}{3^5.2^{14}}\)
\(=2.3^3\)
= 2.27
= 54
Tìm x
a) \(x-\frac{1}{3}=\frac{5}{14}.\left(\frac{-7}{6}\right)\)
b) \(\frac{3}{4}+\frac{1}{4}.x=0,2\)
c) \(\frac{1}{12}.x^2=1.\frac{1}{3}\)
a) x-1/3=5/14.(-7/6)
x-1/3=-5/12
x=-5/12+1/3
x= -1/12
b) 3/4+1/4x=0,2
1/4x=0,2-3/4
1/4x=-11/20
x=-11/20:1-4
x=-11/5
c) 1/12.x^2=1.1/2
1/12.x^2=1/2
x^2= 1/2:1/12
x^2=6
=> x=căn bậc của 6
Chúc bn hok tốt
a)\(x-\frac{1}{3}=\frac{5}{14}\cdot\left(\frac{-7}{6}\right)\)
\(x-\frac{1}{3}=\frac{-5}{12}\)
\(x=\frac{-5}{12}+\frac{1}{3}\)
\(x=\frac{-5}{12}+\frac{4}{12}\)
\(x=\frac{-1}{12}\)
b)\(\frac{3}{4}+\frac{1}{4}\cdot x=0,2\)
\(\frac{3}{4}+\frac{1}{4}\cdot x=\frac{1}{5}\)
\(\frac{1}{4}\cdot x=\frac{1}{5}-\frac{3}{4}\)
\(\frac{1}{4}\cdot x=\frac{4}{20}-\frac{15}{20}\)
\(\frac{1}{4}\cdot x=\frac{-11}{20}\)
\(x=\frac{-11}{20}\cdot4\)
\(x=-\frac{11}{5}\)
c)\(\frac{1}{12}\cdot x^2=1\cdot\frac{1}{3}\)
\(\frac{1}{12}\cdot x^2=\frac{1}{3}\)
\(x^2=\frac{1}{3}\cdot12\)
\(x^2=4=\left(\pm2\right)^2\)
\(x=\pm2\)
tìm x
a\(\frac{2}{3}x-\frac{5}{6}=-1\frac{1}{2}x+0,75\)
b(5x - 3).(2x + 5) =0
c\(\left(\frac{5}{6}:x-1\frac{1}{4}\right)^4=\frac{81}{16}\)
d∣\(\frac{2}{5}\)x−0,2∣.\(1\frac{1}{4}\)- 2 =1,5
Ta có : \(\left(5x-3\right)\left(2x+5\right)=0\)
\(\Leftrightarrow\orbr{\begin{cases}5x-3=0\\2x+5=0\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}5x=3\\2x=-5\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}x=\frac{3}{5}\\x=-\frac{5}{2}\end{cases}}\)
Tìm x biết :
4,\(\frac{\left(-3\right)^x}{81}=-27\)
5,\(1\frac{1}{2}.x-4=0,5\)
6,\(2^{x-1}=16\)
7,\(\left(x-1\right)^2=25\)
8,\(|2x-1|=5\)
9,\(0,2-|4,2-2x|=0\)
11,\(1\frac{2}{3}:\frac{x}{4}=6:0,3\)
12,\(2\frac{2}{3}:x=1\frac{7}{9}:2\frac{2}{3}\)
1) Giải các pt sau:
a) \(\frac{x-3}{5}=6-\frac{1-2x}{3}\)
b) \(\frac{3x-2}{6}-5=\frac{3-2\left(x+7\right)}{4}\)
c) \(\frac{x+8}{6}-\frac{2x-5}{5}=\frac{x-1}{3}-x+7\)
d) \(\frac{7x}{8}-5\left(x-9\right)=\frac{2x+1,5}{6}\)
e) \(\frac{5\left(x-1\right)+2}{6}-\frac{7x-1}{4}=\frac{2\left(2x+1\right)}{7}-5\)
f) \(\frac{x+1}{3}+\frac{3\left(2x+1\right)}{4}=\frac{2x+3\left(x+1\right)}{6}+\frac{7+12x}{12}\)
a, \(\frac{x-3}{5}\) = 6 - \(\frac{1-2x}{3}\)
⇔ 3(x - 3) = 90 - 5(1 - 2x)
⇔ 3x - 9 = 90 - 5 + 10x
⇔ 3x - 10x = 90 - 5 + 9
⇔ -7x = 94
⇔ x = \(\frac{-94}{7}\)
S = { \(\frac{-94}{7}\) }
b, \(\frac{3x-2}{6}\) - 5 = \(\frac{3-2\left(x+7\right)}{4}\)
⇔ 2(3x - 2) - 60 = 9 - 6(x + 7)
⇔ 6x - 4 - 60 = 9 - 6x - 42
⇔ 6x + 6x = 9 - 42 + 60 + 4
⇔ 12x = 31
⇔ x = \(\frac{31}{12}\)
S = { \(\frac{31}{12}\) }
c, \(\frac{x+8}{6}\) - \(\frac{2x-5}{5}\) = \(\frac{x+1}{3}\) - x + 7
⇔ 5(x+ 8) - 6(2x - 5) = 10(x+1) - 30x+210
⇔ 5x+ 40 - 12x+ 30 = 10x+ 10 - 30x+210
⇔ 5x - 12x - 10x+ 30x = 10+ 210 - 30- 40
⇔ 13x = 150
⇔ x = \(\frac{150}{13}\)
S = { \(\frac{150}{13}\) }
d, \(\frac{7x}{8}\) - 5(x - 9) = \(\frac{2x+1,5}{6}\)
⇔ 21x - 120(x - 9) = 4(2x + 1,5)
⇔ 21x - 120x + 1080 = 8x + 6
⇔ 21x - 120x - 8x = 6 - 1080
⇔ -107x = -1074
⇔ x = \(\frac{1074}{107}\)
S = { \(\frac{1074}{107}\) }
e, \(\frac{5\left(x-1\right)+2}{6}\) - \(\frac{7x-1}{4}\) = \(\frac{2\left(2x+1\right)}{7}\) - 5
⇔ 140(x-1)+56 - 42(7x-1) = 48(2x+1)-840
⇔ 140x -140+56 -294x+42= 96x+48 -840
⇔ 140x -294x -96x = 48 -840 -42 -56+140
⇔ -250x = -750
⇔ x = 3
S = { 3 }
f, \(\frac{x+1}{3}\) + \(\frac{3\left(2x+1\right)}{4}\) = \(\frac{2x+3\left(x+1\right)}{6}\) + \(\frac{7+12x}{12}\)
⇔ 4(x+1)+9(2x+1) = 4x+6(x+1)+7+12x
⇔ 4x+4+18x+9 = 4x+6x+6+7+12x
⇔ 4x+18x - 4x - 6x - 12x = 6+7- 9 - 4
⇔ 0x = 0
S = R
Chúc bạn học tốt !
f.$\frac{7x-1}{6}$ =$\frac{16-x}{5}$
g. $\frac{x-3}{5}$ =6-$\frac{1-2x}{3}$
h. $\frac{3x-2}{6}$ -5=$\frac{3-2(x+7)}{4}$
giúp vs ạ, cần gấp
f: =>35x-5=96-6x
=>41x=101
hay x=101/41
g: =>3(x-3)=90-5(1-2x)
=>3x-9=90-5+10x
=>3x-9=10x+85
=>-7x=94
hay x=-94/7
h.3x - 2/6 - 5 = 3 - 2(x + 7)/4
<=> 3x - 2 - 30/6 = 3 - 2(x + 7)/4
<=> 3x - 32/6 = 3 - 2x - 14/4
<=> 3x - 32/6 = -2x - 11/4
<=> 6x - 64/12 = -6x - 33/12
<=> 6x - 64 = -6x - 33 <=> 12x = 31 <=> x = 31/12
\(A=\left(6:\frac{3}{5}-1\frac{1}{6}x\frac{6}{7}\right):\left(4\frac{1}{5}x\frac{10}{11}+5\frac{2}{11}\right)\)\(B=\left(1-\frac{1}{2}\right)x\left(1-\frac{1}{4}\right)x.......x\left(1-\frac{1}{2015}\right)x\left(1-\frac{1}{2016}\right)\)
\(C=5\frac{9}{10}:\frac{3}{2}-\left(2\frac{1}{3}x4\frac{1}{2}-2x2\frac{1}{3}\right):\frac{7}{4}\)