Tìm x biết:
x : 5 = 75
Tìm x,biết:
x +1 : 0, 75 =1, 4 : 0, 25
x + 1 : 0,75 = 1,4 : 0,25
<=> \(x+\dfrac{4}{3}=5,6\)
<=> \(x=\dfrac{64}{15}\)
Tìm x, biết:x-(5/6-x)=x-2/3
`x-(5/6 -x) =x-2/3`
`x-5/6 +x -x+2/3 =0`
`x = 5/6-2/3 = 5/6 -4/6 = 1/6`
bạn có thể giải chi tiết hơn dc ko TV Cuber
tìm [x] biết:
x- \(\dfrac{8}{5}\) < -6 < x
Ta có :
\(x-\dfrac{8}{5}< -6\\ \Rightarrow x< -6+\dfrac{8}{5}\\ \Rightarrow x< -\dfrac{22}{5}=-4\dfrac{2}{5}\\ \Rightarrow-6< x< -1\dfrac{2}{5}\\ \Rightarrow x=-5\)
Vậy...
Tìm [x], biết:
x - \(\dfrac{8}{5}\) < -6 < x
\(\Rightarrow\left\{{}\begin{matrix}x-\dfrac{8}{5}< -6\\-6< x\end{matrix}\right.\\ \Rightarrow\left\{{}\begin{matrix}x< -6+\dfrac{8}{5}\\x>-6\end{matrix}\right.\\ \Rightarrow\left\{{}\begin{matrix}x< -\dfrac{22}{5}\\x>-6\end{matrix}\right.\\ \Rightarrow-6< x< -\dfrac{22}{5}\)
Tìm x biết:x-3/x+5=5/7
\(\frac{x-3}{x+5}=\frac{5}{7}\Rightarrow7\cdot\left(x-3\right)=5\cdot\left(x+5\right)\Rightarrow7x-21=5x+25\Rightarrow7x-5x=25+21\Rightarrow2x=46\Rightarrow x=\frac{46}{2}=23\)
Tìm x biết:
x(x+5)(x-5)-(x+2)(x^2-2x+4)=42
\(x\left(x+5\right)\left(x-5\right)-\left(x+2\right)\left(x^2-2x+4\right)=42\)
\(\Leftrightarrow x\left(x^2-25\right)-\left(x^3+8\right)=42\)
\(\Leftrightarrow x^3-25x-x^3-8=42\)
\(\Leftrightarrow-25x-8=42\)
\(\Leftrightarrow-25x=42+8\)
\(\Leftrightarrow-25x=50\)
\(\Leftrightarrow x=-\dfrac{50}{25}=-2\)
Tìm x,biết:x.(x-5)+x-5=0
x.(x-5)+x-5=o
=> x.(x-5)+(x-5)=0
=>(x-5)(x+1)=0
=> x-5=0 =>x=5
x+1=0 x=-1
x ( x - 5 ) + x - 5 = 0
x ( x - 5 ) + ( x - 5 ) = 0
(x - 5 ) ( x + 1 ) = 0
\(\Rightarrow\orbr{\begin{cases}x-5=0\\x+1=0\end{cases}\Rightarrow\orbr{\begin{cases}x=5\\x=-1\end{cases}}}\)
Vậy...
\(x.\left(x-5\right)+x-5=0\)
\(\Leftrightarrow x.\left(x-5\right)+\left(x-5\right)=0\)
\(\Leftrightarrow\left(x-5\right).\left(x+1\right)=0\)
\(\Leftrightarrow\orbr{\begin{cases}x-5=0\\x+1=0\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}x=5\\x=-1\end{cases}}\)
Tìm số Z x, biết:
x . 2 - 5 . x = 0
tìm x biết:
x: 2/3 = 5/2
\(x\div\dfrac{2}{3}=\dfrac{5}{2}\)
\(x=\dfrac{2}{3}\times\dfrac{5}{2}\)
\(x=\dfrac{5}{3}\)
Tìm x,y biết:
x/y=-2/5