2,5+-7/3x=1/2+x
a)0,5x-2/3x=7/12
b)x:4/1/3=-2,5
c)5,5x=13/15
d) (3x/7+1):(-4)=-1/28
bn đừng nói ai xin lỗi với mình nữa nhé ! trả lời nick mình rồi mình sẽ nói cho
a) 0,5x-2/3x=7/12
b) x:4/1/3=-2,5
c)5,5x=13/15
d) (3x/7+1):(-4)=-1/28
0,5x - 2 phần 3x = 7 phần 12
x:4 1 phần 3 = -2,5
5,5x = 13 phần 15
( 3x phần 7 + 1 ) : (-4) = -1 phần 28
tìm x
a) x/7 = 6/21
b)2/3x -1/2=1/10
c)1/4+1/3 : x = -5
d)3x+17=2
đ)2/3x +1/4 =7/12
2x+3/10= 11/6 . 6/11
x : 4 1/3 = -2,5
a) x/7 = 6/21
x/7 = 2/7
=>x=2
b)2/3x -1/2=1/10
2/3x = 1/10+1/2
2/3x = 3/5
x=3/5:2/3
x=9/10
c)1/4+1/3 : x = -5
d)3x+17=2
đ)2/3x +1/4 =7/12
2x+3/10= 11/6 . 6/11
x : 4 1/3 = -2,5
a) x/7 = 6/21
x/7 = 2/7
=>x=2
b)2/3x -1/2=1/10
2/3x = 1/10+1/2
2/3x = 3/5
x=3/5:2/3
x=9/10
c)1/4+1/3 : x = -5
d)3x+17=2
đ)2/3x +1/4 =7/12
2x+3/10= 11/6 . 6/11
x : 4 1/3 = -2,5
Tìm x biết :
a, 0,5x - 2/3x=7/12
b, x:4 và 1/3=-2,5
c, 5,5x=13/15
d, ( 3x/7+1):(-4)=-1/28
a: =>1/2x-2/3x=7/12
=>-1/6x=7/12
hay x=-7/2
b: \(\Leftrightarrow x=-\dfrac{5}{2}\cdot\dfrac{13}{3}=\dfrac{-65}{6}\)
c: =>x=13/15:11/2=26/165
d: =>3/7x+1=1/7
=>3/7x=-6/7
hay x=-2
Rút gọn biểu thức
a) 7x(4y-x) + 4y (y-7x) - (2y^2 -3,5x)
b) 3x(5x^2 -2) -5x^2 (7+3x) -2,5( 2-14x^2)
c) 2x^3 (x-1) (x+1) -5x(x+1)
Tìm biểu thức 3x(5x^2-2)-5x^2(7+3x)-2,5(2-14x^2) với x=-2
\(=15x^3-6x-35x^2-15x^3-5+35x^2=-6x-5\\ =-6\left(-2\right)-5=7\)
Rút gọn biểu thức
a) 7x(4y-x) + 4y (y-7x) - (2y^2 -3,5x)
b) 3x(5x^2 -2) -5x^2 (7+3x) -2,5( 2-14x^2)
c) 2x^3 (x-1) (x+1) -5x(x+1)
(1/3x -8/15) (2,5 + -7/5 : x)=0
\(\Rightarrow\left[{}\begin{matrix}\dfrac{1}{3}x-\dfrac{8}{15}=0\\2,5+\left(-\dfrac{7}{5}\right)\div x=0\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}\dfrac{1}{3}x=0+\dfrac{8}{15}\\-\dfrac{7}{5}\div x=0-2,5\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}\dfrac{1}{3}x=\dfrac{8}{15}\\-\dfrac{7}{5}\div x=-2,5\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=\dfrac{8}{15}\div\dfrac{1}{3}\\x=-\dfrac{7}{5}\div\left(-2,5\right)\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=\dfrac{8}{5}\\x=\dfrac{14}{25}\end{matrix}\right.\)