Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
\(\frac{15}{26}+\frac{x}{16}=\frac{46}{52}\)
\(\frac{x}{16}=\frac{46}{52}-\frac{15}{26}\)
\(\frac{x}{16}=\frac{4}{13}\)
\(< =>\frac{x}{208}=\frac{64}{208}=\frac{4}{13}\)
\(x=4\)
\(\frac{15}{26}+\frac{x}{16}=\frac{46}{52}\)
\(\Rightarrow\frac{15}{26}+\frac{x}{16}=\frac{23}{26}\)
\(\Rightarrow\frac{x}{16}=\frac{23}{26}-\frac{15}{26}\)
\(\Rightarrow\frac{x}{16}=\frac{4}{13}\)
\(\Rightarrow13x=4.16\)
\(\Rightarrow13x=64\)
\(\Rightarrow x=64:13\)
\(\Rightarrow x=\frac{64}{13}\)
Vậy x = \(\frac{64}{13}\)
_Chúc bạn học tốt_
\(D=\frac{1}{6}+\frac{1}{66}+\frac{1}{176}+\frac{1}{336}+\frac{1}{546}\)
\(D=\frac{1}{1.6}+\frac{1}{6.11}+\frac{1}{11.16}+\frac{1}{16.21}+\frac{1}{21.26}\)
\(D=\frac{1}{5}\left(\frac{5}{1.6}+\frac{5}{6.11}+\frac{5}{11.16}+\frac{5}{16.21}+\frac{5}{21.26}\right)\)
\(D=\frac{1}{5}\left(\frac{1}{1}-\frac{1}{6}+\frac{1}{6}-\frac{1}{11}+...+\frac{1}{21}-\frac{1}{26}\right)\)
\(D=\frac{1}{5}\left(\frac{1}{1}-\frac{1}{26}\right)\)
\(D=\frac{1}{5}.\frac{25}{26}=\frac{5}{26}\)
\(-52+\frac{2}{3}x=-46\)
\(\frac{2}{3}x=-46+52\)
\(\frac{2}{3}x=6\)
\(x=6:\frac{2}{3}\)
\(x=9\)
a) \(\frac{3}{4}.x+40\%=\frac{-1}{4}\)
\(\frac{3}{4}.x+\frac{2}{5}=\frac{-1}{4}\)
\(\frac{3}{4}.x=\frac{-13}{20}\)
\(x=\frac{-13}{15}\)
Vậy \(x=\frac{-13}{15}\)
c) \(|x-1|=2^3+\left(-5\right)\)
\(|x-1|=3\)
\(\Leftrightarrow\orbr{\begin{cases}x-1=3\\x-1=-3\end{cases}\Leftrightarrow\orbr{\begin{cases}x=4\\x=-2\end{cases}}}\)
Vậy \(x\in\left\{-2;4\right\}\)
a) \(\left(x+\frac{5}{3}\right)\cdot\frac{9}{13}=\frac{2}{3}\)
\(x+\frac{5}{3}=\frac{2}{3}:\frac{9}{13}\)
\(x+\frac{5}{13}=\frac{26}{27}\)
\(x=\frac{5}{13}-\frac{26}{27}\)
\(x=\frac{-203}{351}\)
b) \(43770:x=560-434\)
\(43770:x=126\)
\(x=43770:126\)
\(x=\frac{7295}{21}\)
c) \(x:3\frac{1}{3}=2\frac{2}{5}+\frac{7}{10}\)
\(x:\frac{10}{3}=\frac{12}{5}+\frac{7}{10}\)
\(x:\frac{10}{3}=\frac{31}{10}\)
\(x=\frac{31}{10}\cdot\frac{10}{3}\)
\(x=\frac{31}{3}\)
n)
\(5^x:5^2=25\)
\(\Rightarrow5^{x-2}=5^2\)
=> x - 2 =2
=>x=4
m)
\(1+2+....+x=78\)
\(\Rightarrow\frac{\left(x+1\right)x}{2}=78\)
\(\Rightarrow\left(x+1\right)x=156\)
\(\Rightarrow\left(x+1\right)x=12.13\)
=> x=12
o)
\(\left(2+x\right)+\left(4+x\right)+....+\left(52+x\right)=780\)
\(\Rightarrow\left(2+4+6+...+52\right)+26x=780\)
\(\Rightarrow702+26x=780\)
\(\Rightarrow26x=78\)
=>x=3
n) 5x : 52 = 125
=> 5x : 52 = 53
=> 5x-2 = 53
=> x - 2 = 3
=> x = 3 + 2
=> x = 5
m) 1 + 2 + 3 + ... + x = 78
Số lượng số hạng của tổng trên là :
( x - 1 ) + 1 = x ( số hạng )
Số x cần tìm là :
( x + 1 ) . x : 2 = 78
=> ( x + 1 ) . x = 78 . 2
=> ( x + 1 ) . x = 156
=>13 . 12 = 156
=> x = 12
o) ( 2 + x ) + ( 4 + x ) + ( 6 + x ) + ... + ( 52 + x ) = 780
=> 2 + x + 4 + x + 6 + x + ... + 52 + x = 780
=> ( x + x + x + ... + x ) + ( 2 + 4 + 6 + ... + 52 ) = 780
=> 26x + 702 = 780
=> 26x = 780 - 702
=> 26x = 78
=> x = 78 : 26
=> x = 3
\(-52+\frac{2}{3}x=-46\)
\(\frac{2}{3}x=-46-\left(-52\right)\)
\(\frac{2}{3}x=6\)
\(x=6:\frac{2}{3}\)
\(x=9\)
\(\frac{2}{3}\)X=-46-(-52)
\(\frac{2}{3}\)X=6
X=6chia \(\frac{2}{3}\)
X=9