9 - x tren 13-x =1 phan 2 vay x = ... ; 7+y tren 15+y = 1 phan 2 vay x = ...
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
\(\frac{9-x}{13-x}=\frac{1}{2}\Rightarrow2\times\left(9-x\right)=1\times\left(13-x\right)\)
\(2\times9-2\times x=13-x\Rightarrow18-2x=13-x\)
\(2x-x=18-13\Rightarrow x=5\)
a, (1-x)(5x+3)= (3x-8)(1-x)
<=> (1-x) (5x+3) - (3x-8)(1-x) =0 <=> (1-x) (2x+11) = 0
\(\Leftrightarrow\left[{}\begin{matrix}1-x=0\\2x+11=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=1\\x=-\dfrac{11}{2}\end{matrix}\right.\)
Vậy.........
b, (x-3)(x+4)-2(3x-2)=(x-4)^2
<=> 3x = 24<=> x=8
Vậy .......
c,x^2+ x^3+x+1=0
<=> x^2 (x+1) +(x+1) =0 <=> (x^2 +1)(x+1) =0
<=> x+1 =0 => x=-1
Vậy.......
d, \(\dfrac{x-3}{x+3}-\dfrac{2}{x-3}=\dfrac{3x+1}{9-x^2}\)
\(\Leftrightarrow x^2-6x+9-2x-6=-3x-1\)
\(\Leftrightarrow x^2-5x+4=0\Leftrightarrow\left(x+4\right)\left(x-1\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x+4=0\\x-1=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=-4\\x=1\end{matrix}\right.\)
Vậy...........
a. 2x . 7 = 56
2x = 56 : 7
2x = 8
\(\Rightarrow\)23 = 8
Vậy x = 8
\(\frac{4}{\frac{2}{5}}:\left(-\frac{33}{10}\right)+x=-\frac{1}{\frac{5}{6}}\)
\(10:\left(-\frac{33}{10}\right)+x=-\frac{6}{5}\)
\(-\frac{100}{33}+x=-\frac{6}{5}\)
\(x=\frac{302}{165}\)
\(\frac{2^{23}\cdot45^{25}\cdot13^{22}\cdot35^{16}}{9^{26}\cdot65^{22}\cdot28^{17}\cdot25^9}=\frac{2^{23}\cdot5^{25}\cdot3^{50}\cdot13^{22}\cdot5^{16}\cdot7^{16}}{3^{52}\cdot5^{22}\cdot13^{22}\cdot7^{17}\cdot2^{54}\cdot5^{18}}=\frac{2^{23}\cdot3^{50}\cdot5^{31}\cdot7^{16}\cdot13^{22}}{2^{54}\cdot3^{52}\cdot5^{22}\cdot7^{17}\cdot13^{22}}=\frac{5^9}{2^{31}\cdot3^2\cdot7}\)
x= 5
y= 1