.

\(\Leftrightarrow14\sqrt{x+35}+6\sqrt{x+1}-84-\sqrt{\left(x+35\right)\left(x+1\right)}=0\)

\(\Leftrightarrow\left(\sqrt{x+35}-6\right)\left(14-\sqrt{x+1}\right)=0\)

\(\Leftrightarrow x=195;1\)

tick nha

b.

ĐKXĐ: \(x\ge-1\)

\(\sqrt{\left(x+1\right)\left(x+35\right)}-14\sqrt{x+35}+84-6\sqrt{x+1}=0\)

\(\Leftrightarrow\sqrt{x+1}\left(\sqrt{x+35}-14\right)-6\left(\sqrt{x+35}-14\right)=0\)

\(\Leftrightarrow\left(\sqrt{x+1}-6\right)\left(\sqrt{x+35}-14\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}\sqrt{x+1}=6\\\sqrt{x+35}=14\end{matrix}\right.\)

\(\Leftrightarrow...\)

a. ĐKXĐ: \(-1\le x\le1\)

Đặt \(\left\{{}\begin{matrix}\sqrt{x+1}=a\ge0\\\sqrt{1-x}=b\ge0\end{matrix}\right.\)

\(\Rightarrow a+2a^2=-b^2+b+3ab\)

\(\Leftrightarrow\left(2a^2-3ab+b^2\right)+a-b=0\)

\(\Leftrightarrow\left(a-b\right)\left(2a-b\right)+a-b=0\)

\(\Leftrightarrow\left(a-b\right)\left(2a-b+1\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}a=b\\2a+1=b\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}\sqrt{x+1}=\sqrt{1-x}\\2\sqrt{x+1}+1=\sqrt{1-x}\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=0\\4x+5+4\sqrt{x+1}=1-x\left(1\right)\end{matrix}\right.\)

(1) \(\Leftrightarrow4\sqrt{x+1}=-4-5x\) \(\left(x\le-\dfrac{4}{5}\right)\)

\(\Leftrightarrow16\left(x+1\right)=25x^2+40x+16\)

\(\Leftrightarrow25x^2+24x=0\Rightarrow\left[{}\begin{matrix}x=0\left(loại\right)\\x=-\dfrac{24}{25}\end{matrix}\right.\)

c.

ĐKXĐ: \(x\ge-\dfrac{3}{2}\)

\(\Leftrightarrow x\sqrt{2x+3}-\sqrt{2x+3}+3-3x+3\sqrt{x+5}-\sqrt{\left(2x+3\right)\left(x+5\right)}=0\)

\(\Leftrightarrow\sqrt{2x+3}\left(x-1\right)-3\left(x-1\right)-\sqrt{x+5}\left(\sqrt{2x+3}-3\right)=0\)

\(\Leftrightarrow\left(x-1\right)\left(\sqrt{2x+3}-3\right)-\sqrt{x+5}\left(\sqrt{2x+3}-3\right)=0\)

\(\Leftrightarrow\left(x-1-\sqrt{x+5}\right)\left(\sqrt{2x+3}-3\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x-1-\sqrt{x+5}=0\\\sqrt{2x+3}-3=0\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x+5-\sqrt{x+5}-6=0\\\sqrt{2x+3}=3\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}\sqrt{x+5}=-2\left(loại\right)\\\sqrt{x+5}=3\\\sqrt{2x+3}=3\end{matrix}\right.\)

\(\Leftrightarrow...\)

Ta có:

\(\dfrac{3}{x}=\dfrac{y}{35}=\dfrac{-36}{84}\)

\(\Rightarrow\left\{{}\begin{matrix}\dfrac{3}{x}=\dfrac{-36}{84}\\\dfrac{y}{35}=\dfrac{-36}{84}\end{matrix}\right.\)\(\Rightarrow\left\{{}\begin{matrix}3.84=-36.x\\y.84=-36.35\end{matrix}\right.\)

\(\Rightarrow\left\{{}\begin{matrix}x=\dfrac{3.84}{-36}\\y=\dfrac{-36.35}{84}\end{matrix}\right.\)\(\Rightarrow\left\{{}\begin{matrix}x=-7\\y=-15\end{matrix}\right.\)

Vậy: \(\left\{{}\begin{matrix}x=-7\\y=-15\end{matrix}\right.\)

thui khỏi TLCH nữa t TLCH r

Ta có: -36/84=-3/7

=> 3/x=y/35=-3/7

3/x=-3/7

=> 3.7=-3.x

=> 21=-3.x

=> 21:(-3)=x

=> x=-7

   y/35=-3/7

=> y.7=35.(-3)

=> y.7=-105

=> y   =-105:7

=> y   =-15

Vậy x=-7;y=-15

Cách nhanh hơn là:-36/84=-3/7

3/x=-3/7 suy ra x=-7

y/35=-3/7suy ra y=-15

 -36/84 = -3/7 
3/x = -3/7 => x = -7 
y/35 = -3/7 => y = -15

Bạn onl sớm thế??

ko ro de bai

3/x=y/35=-36/84 => x=3.84/-36

y=35.84/ -36

đề gì mà củ chuối thế