PT
0
K
Khách
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
Các câu hỏi dưới đây có thể giống với câu hỏi trên
PT
0
10 tháng 2 2016
bài 1 : a,ta có 3/x-1 =4/y-2=5/z-3 => x-1/3=y-2/4=z-3/5
áp dụng .... => x-1+y-2+z-3 / 3+4+5 = x+y+z-1-2-3/3+4+5 = 12/12=1
do x-1/3 = 1 => x-1 = 3 => x= 4 ( tìm y,z tương tự
24 tháng 3 2021
Bài 1:
a) Ta có: 3/x - 1 = 4/y - 2 = 5/z - 3 => x - 1/3 = y - 2/4 = z - 3/5 áp dụng ... =>x - 1 + y - 2 + z - 3/3 + 4 + 5 = x + y + z - 1 - 2 - 3/3 + 4 + 5 = 12/12 = 1 do x - 1/3 = 1 => x - 1 = 3 => x = 4 ( tìm y, z tương tự )
NL
1
VM
1 tháng 11 2019
Bài 1:
\(\left(-2\right)^3.\left(\frac{3}{4}-0,25\right):\left(\frac{9}{4}-\frac{7}{6}\right)\)
\(=\left(-8\right).\left(\frac{3}{4}-\frac{1}{4}\right):\left(\frac{9}{4}-\frac{7}{6}\right)\)
\(=\left(-8\right).\frac{1}{2}:\frac{13}{12}\)
\(=\left(-4\right):\frac{13}{12}\)
\(=-\frac{48}{13}.\)
Bài 2:
a) \(4\frac{1}{3}:\frac{x}{4}=6:0,3\)
\(\Rightarrow\frac{13}{3}:\frac{x}{4}=6:0,3\)
\(\Rightarrow\frac{\frac{13}{3}}{\frac{x}{4}}=\frac{6}{0,3}\)
\(\Rightarrow\frac{13}{3}.0,3=6.\frac{x}{4}\)
\(\Rightarrow\frac{13}{10}=6.\frac{x}{4}\)
\(\Rightarrow\frac{x}{4}=\frac{13}{10}:6\)
\(\Rightarrow\frac{x}{4}=\frac{13}{60}\)
\(\Rightarrow x.60=13.4\)
\(\Rightarrow x.60=52\)
\(\Rightarrow x=52:60\)
\(\Rightarrow x=\frac{13}{15}\)
Vậy \(x=\frac{13}{15}.\)
b) \(\left(2^3:4\right).2^{x+1}=64\)
\(\Rightarrow\left(2^3:2^2\right).2^{x+1}=64\)
\(\Rightarrow2^1.2^{x+1}=64\)
\(\Rightarrow2^1.2^{x+1}=2^6\)
\(\Rightarrow1+x+1=6\)
\(\Rightarrow\left(1+1\right)+x=6\)
\(\Rightarrow2+x=6\)
\(\Rightarrow x=6-2\)
\(\Rightarrow x=4\)
Vậy \(x=4.\)
Chúc em học tốt!
1 tháng 11 2019
(−2)3.(34−0,25):(94−76)(−2)3.(34−0,25):(94−76)
=(−8).(34−14):(94−76)=(−8).(34−14):(94−76)
=(−8).12:1312=(−8).12:1312
=(−4):1312=(−4):1312
=−4813.=−4813.
Bài 2:
a) 413:x4=6:0,3413:x4=6:0,3
⇒133:x4=6:0,3⇒133:x4=6:0,3
⇒133x4=60,3⇒133x4=60,3
⇒133.0,3=6.x4⇒133.0,3=6.x4
⇒1310=6.x4⇒1310=6.x4
⇒x4=1310:6⇒x4=1310:6
⇒x4=1360⇒x4=1360
⇒x.60=13.4⇒x.60=13.4
⇒x.60=52⇒x.60=52
⇒x=52:60⇒x=52:60
⇒x=1315⇒x=1315
Vậy x=1315.x=1315.
b) (23:4).2x+1=64(23:4).2x+1=64
⇒(23:22).2x+1=64⇒(23:22).2x+1=64
⇒21.2x+1=64⇒21.2x+1=64
⇒21.2x+1=26⇒21.2x+1=26
⇒1+x+1=6⇒1+x+1=6
⇒(1+1)+x=6⇒(1+1)+x=6
⇒2+x=6⇒2+x=6
⇒x=6−2⇒x=6−2
⇒x=4⇒x=4
Vậy x=4.x=4.
25 tháng 10 2018
a) \(4\dfrac{1}{3}:\dfrac{x}{4}=6:0,3\)
\(\dfrac{13}{3}:\dfrac{x}{4}=20\)
\(\dfrac{x}{4}=\dfrac{13}{3}:20\)
\(\dfrac{x}{4}=\dfrac{13}{3}\cdot\dfrac{1}{20}\)
\(\dfrac{x}{4}=\dfrac{13}{60}\)
\(x=\dfrac{13}{60}\cdot4\)
Vậy \(x=\dfrac{13}{15}\)
b)\(2^3:4.2^{\left(x+1\right)}=64\)
\(8:4.2^{\left(x+1\right)}=64\)
\(2.2^{\left(x+1\right)}=64\)
\(2\cdot2^x.2=64\)
\(4.2^x=64\)
\(2^x=64:4\)
\(2^x=16\)
\(2^x=2^4\)
Vậy \(x=4\)
MH
28 tháng 9 2015
a.=> \(\frac{\left(\frac{1}{3}\right).x}{\frac{2}{3}}=\frac{\frac{7}{4}}{\frac{2}{5}}\)
=> \(\frac{1}{3}.x=\frac{7}{4}.\frac{2}{3}:\frac{2}{5}\)
=>\(\frac{1}{3}.x=\frac{35}{12}\)
=> x\(=\frac{35}{12}:\frac{1}{3}\)
Vậy x=\(\frac{35}{4}\).
b. => \(\frac{4,5}{0,3}=\frac{2,25}{0,1.x}\)
=>\(0,1.x=\frac{2,25.0,3}{4,5}\)
=>\(0,1.x=0,15\)
=>\(x=0,15:0,1\)
Vậy x=1,5
c. =>\(\frac{8}{\frac{1}{4}.x}=\frac{2}{0,02}\)
=>\(\frac{1}{4}.x=\frac{8.0,02}{2}\)
=>\(\frac{1}{4}.x=0,08\)
=>\(x=0,08:\frac{1}{4}\)
Vậy x=0,32.
d. =>\(\frac{3}{\frac{9}{4}}=\frac{\frac{3}{4}}{6.x}\)
=>\(3.6x=\frac{9}{4}.\frac{3}{4}\)
=>\(18x=\frac{27}{16}\)
=>\(x=\frac{27}{16}:18\)
Vậy x=\(\frac{3}{32}\)
SH
14 tháng 10 2018
Bai 1: \(\left(-2\right)^3.\left(\dfrac{3}{4}-0,25\right):\left(2\dfrac{1}{4}-1\dfrac{1}{6}\right)\)
\(=\left(-8\right).\left(\dfrac{3}{4}-\dfrac{1}{4}\right):\left(\dfrac{9}{4}-\dfrac{7}{6}\right)\)
\(=\left(-8\right).\dfrac{1}{2}:\left(\dfrac{27}{12}-\dfrac{14}{12}\right)\)
\(=\left(-4\right):\dfrac{13}{12}\)
\(=\left(-4\right).\dfrac{12}{13}\)
\(=\dfrac{-48}{13}\)
Bai 2:
\(a,4\dfrac{1}{3}:\dfrac{x}{4}=6:0,3\)
\(\dfrac{13}{3}:\dfrac{x}{4}=20\)
\(\dfrac{x}{4}=\dfrac{13}{3}:20\)
\(\dfrac{x}{4}=\dfrac{13}{60}\)
➩ \(x.60=4.13\) ➩ \(x.60=52\) ➩ \(x=\dfrac{13}{15}\)
Vay \(x=\dfrac{13}{15}\)
\(b,\left(2^3:4\right).2^{\left(x+1\right)}=64\)
\(\left(8:4\right).2^{x+1}=64\)
\(2.2^{x+1}=64\)
\(2^{x+1}=32\)
➩ \(2^{x+1}=2^5\) ➩ \(x+1=5\) ➩ \(x=4\)
Vay \(x=4\)
NC
7 tháng 8 2018
a) \(\left(x+5\right)^3=64\)
\(\Leftrightarrow\left(x+5\right)^3=4^3\)
\(\Leftrightarrow x+5=4\)
\(\Leftrightarrow x=-1\)
Vậy x = - 1
b) \(x:\left(-\frac{3}{5}\right)^2=-\frac{3}{5}\)
\(\Leftrightarrow x=\left(-\frac{3}{5}\right)^2.\left(-\frac{3}{5}\right)\)
\(\Leftrightarrow x=\left(-\frac{3}{5}\right)^3\)
\(\Leftrightarrow x=-0,216\)
Vậy x = - 0, 216
c) \(\left(\frac{4}{7}\right)^4.x=\left(\frac{4}{7}\right)^6\)
\(\Leftrightarrow x=\left(\frac{4}{7}\right)^6:\left(\frac{4}{7}\right)^4\)
\(\Leftrightarrow x=\left(\frac{4}{7}\right)^2\)
\(\Leftrightarrow\text{x}=\frac{16}{49}\)
Vậy x = 16/49
d) \(\left(-\frac{1}{3}\right)^3x=\frac{1}{81}\)
\(\Leftrightarrow-\frac{1}{27}x=\frac{1}{81}\)
\(\Leftrightarrow x=\frac{1}{81}:\left(-\frac{1}{27}\right)\)
\(\Leftrightarrow x=-\frac{1}{3}\)
Vậy x = - 1/3
17 tháng 8 2016
a) \(\left(\frac{1}{3}.x\right):\frac{2}{3}=\frac{7}{4}:\frac{2}{5}\)
\(\left(\frac{1}{3}.x\right):\frac{2}{3}=\frac{35}{8}\)
\(\Rightarrow\frac{1}{3}.x=\frac{35}{8}.\frac{2}{3}\)
\(\Rightarrow\frac{1}{3}.x=\frac{35}{12}\)
\(\Rightarrow x=\frac{35}{12}:\frac{1}{3}\)
\(\Rightarrow x=\frac{35}{4}\)
Vậy \(x=\frac{35}{4}\)