
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.


Trả lời :
a, \(\frac{3}{4}-\left(\frac{1}{2}\div x+\frac{1}{2}\right)=\frac{3}{5}\)
=> \(\frac{1}{2}\div x+\frac{1}{2}=\frac{3}{20}\)
=> \(\frac{1}{2}\div x=\frac{-7}{20}\)
=> \(x=\frac{-10}{7}\)
b, (4 - x) . (2x + 3) = 0
=> \(\orbr{\begin{cases}4-x=0\\2x+3=0\end{cases}}\)
=> \(\orbr{\begin{cases}x=4\\x=\frac{-3}{2}\end{cases}}\)
c, \(\frac{4}{-3}=\frac{-12}{x}\)
=> 4x = 36
=> x = 9
d, \(\frac{4x}{-3}=\frac{12}{-x}\)
=> \(-4x^2=-36\)
=> 4x2 = 36
=> x2 = 9
=> x = \(\pm3\)


a, Áp dụng tính chất dãy tỉ số bằng nhau ta có :
\(\frac{x}{3}=\frac{y}{-2}=\frac{2x+5y}{2.3+5.\left(-2\right)}=-\frac{12}{-4}=3\)
\(x=-3;y=6\)
b, Theo bài ra ta có : \(x:y=4:5\Leftrightarrow\frac{x}{4}=\frac{y}{5}\)
Áp dụng tính chất dãy tỉ số bằng nhau ta có :
\(\frac{x}{4}=\frac{y}{5}=\frac{x-y}{4-5}=\frac{13}{-1}=-13\)
\(x=-52;y=-65\)
c, Theo bài ra ta có: \(4x=7y\Leftrightarrow\frac{x}{7}=\frac{y}{4}\)
Áp dụng tính chất dãy tỉ số bằng nhau ta có :
\(\frac{x}{7}=\frac{y}{4}=\frac{x-y}{7-4}=\frac{12}{3}=4\)
\(x=28;y=16\)

\(\frac{35}{x}=\frac{15}{12}\Leftrightarrow x=35.12:15=28\)
\(-\frac{2,6}{x}=-\frac{12}{42}\Leftrightarrow\frac{-2,6}{x}=-\frac{2}{7}\Leftrightarrow x=-2,6.7:\left(-2\right)=\frac{91}{10}\)
\(\frac{125}{10}=\frac{x}{45}\Leftrightarrow x=125.45:10=562,5\)
\(\frac{x^2}{6}=\frac{24}{25}\Leftrightarrow x^2=6.24:25=\frac{144}{25}\Leftrightarrow x=\sqrt{\frac{144}{25}}\Leftrightarrow x=\frac{12}{5}\)
1; \(\dfrac{35}{x}\) = \(\dfrac{15}{12}\) (\(x\ne\) 0)
⇒ \(x\) = 35 : \(\dfrac{15}{12}\)
⇒ \(x\) = 28
Vậy \(x=28\)

a ) x + 5/12 = -2/3
=> x = -2/3 - 5/12
=> x = -8/12 - 5/12
=> x = -13/12
b ) 4/5 + 3/4 : x = 1/2
=> 3/4 : x = 1/2 - 4/5
=> 3/4 : x = 5/10 - 8/10
=> 3/4 : x = -3/10
=> x = 3/4 : -3/10
=> x = -5/2
c ) x/2 + x/3 = 1/4
=> 3x/6 + 2x/6 = 1/4
=> ( 3x + 2x )/6 = 1/4
=> 5x/6 = 1/4
=> 20x/24 = 6/24
=> 20x = 6
=> x = 6 : 20
=> x = 0 , 3
Chúc bạn học giỏi !!!

a)
\(\left|x-5\right|=4\)
\(\Rightarrow\left[\begin{array}{nghiempt}x-5=4\\x-5=-4\end{array}\right.\)\(\Rightarrow\left[\begin{array}{nghiempt}x=9\\x=1\end{array}\right.\)
Vậy x = 9 ; x = 1
b)
\(\left|x+9\right|=12\)
\(\Rightarrow\left[\begin{array}{nghiempt}x+9=12\\x+9=-12\end{array}\right.\)\(\Rightarrow\left[\begin{array}{nghiempt}x=3\\x=-21\end{array}\right.\)
Vậy x = 3 ; x = - 21
\(\left|x-5\right|=4\)
\(\Rightarrow\left[\begin{array}{nghiempt}x-5=4\\x-5=-4\end{array}\right.\) \(\Rightarrow\left[\begin{array}{nghiempt}x=4+5\\x=-4+5\end{array}\right.\)
\(\Rightarrow\left[\begin{array}{nghiempt}x=9\\x=1\end{array}\right.\)
Vậy: \(x\in\left\{1;9\right\}\)
\(\left|x+9\right|=12\)
\(\Rightarrow\left[\begin{array}{nghiempt}x+9=12\\x+9=-12\end{array}\right.\) \(\Rightarrow\left[\begin{array}{nghiempt}x=12-9\\x=-12-9\end{array}\right.\)
\(\Rightarrow\left[\begin{array}{nghiempt}x=3\\x=-21\end{array}\right.\)
Vậy: \(x\in\left\{-21;3\right\}\)
x^4=x^12
=> x1 = 8
=> x2 = 2
=> 8^4= 2 ^12
x= 0 , 1
vì hai số này bình mấy lần cũng ra kết quả là chính nó