\(\frac{13x-2}{2x+5}=-\frac{27}{5-x}\)ĐK : \(x\ne-\frac{5}{2};5\)

\(\Rightarrow\left(13x-2\right)\left(5-x\right)=-27\left(2x+5\right)\)

\(\Leftrightarrow65x-13x^2-10+2x=-54x-135\)

\(\Leftrightarrow-13x^2+121x+125=0\Leftrightarrow x=10,24...;x=-0,93...\)

\(\frac{2x-10}{6}=\frac{-27}{5-x}\)

\(\frac{2\left(x-5\right)}{6}=\frac{27}{x-5}\)

\(2\left(x-5\right)^2=27\times6\)

\(2x^2-20x+50-162=0\)

\(2x^2-20x-112=0\)

\(x^2-10x-56=0\)

\(x^2-14x+4x-56=0\)

\(\left(x-14\right)\left(x+4\right)=0\)

\(\Leftrightarrow\orbr{\begin{cases}x-14=0\\x+4=0\end{cases}}\Leftrightarrow\orbr{\begin{cases}x=14\\x=-4\end{cases}}\)

KL .....

XIN TIICK

a, Đặt \(P\left(x\right)=2x+6=0\Leftrightarrow x=-3\)

b, Đặt \(A\left(x\right)=3x^2+1=0\)

mà \(3x^2\ge0\forall x\Rightarrow3x^2+1>0\forall x\)

Vậy đa thức ko có nghiệm 

c, \(B\left(x\right)=8x^2+11x+3=0\Leftrightarrow8x^2+8x+3x+3=0\)

\(\Leftrightarrow8x\left(x+1\right)+3\left(x+1\right)=0\Leftrightarrow\left(8x+3\right)\left(x+1\right)=0\Leftrightarrow x=-\frac{3}{8};x=-1\)

= 9 . \(\frac{1}{5}\) - 6 + 9 . \(\frac{4}{5}\)

= \(\frac{9}{5}\) - 6 + \(\frac{36}{5}\)

= 9 - 6

= 3

Học tốt

\(\frac{-2}{5}.\frac{1}{3}-\frac{1}{3}:\frac{5}{2}\)

\(=\frac{-2}{5}.\frac{1}{3}-\frac{1}{3}.\frac{2}{5}\)

\(=\left(\frac{-2}{5}-\frac{2}{5}\right).\frac{1}{3}\)

\(=\frac{-4}{5}.\frac{1}{3}\)

\(=\frac{-4}{15}\)

   -2/5 x 1/3 - 1/3 : 5/2

= -2/5 x 1/3- 1/3 x 2/5

= 1/3 x (-2/5 - 2/5)

= 1/3 x -4/5

= -4/15

Cái gì vậy chơi bài có qué mà chị cho em kết bạn nhé

oki em

có nha bạn

Ta có \(x< y\Rightarrow a< b\)

\(z-x=\frac{a+b}{2m}-\frac{a}{m}=\frac{a+b-2a}{2m}=\frac{b-a}{2m}\)

\(a< b\Rightarrow b-a>0;m>0\Rightarrow2m>0\Rightarrow z-x=\frac{b-a}{2m}>0\Rightarrow z>x\)

\(z-y=\frac{a+b}{2m}-\frac{b}{m}=\frac{a+b-2b}{2m}=\frac{a-b}{2m}\)

\(a< b\Rightarrow a-b< 0;m>0\Rightarrow2m>0\Rightarrow z-y=\frac{a-b}{2m}< 0\Rightarrow z< y\)

\(\Rightarrow x< z< y\)