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ai tik mik mik tik lại cho

Người ta giúp bạn, bạn còn đặt điều kiện. bạn thicks tích cho ai thì tick điều đó đâu có sao. Nhưng bạn ra giá vậy sau chẳng ai giúp bạn đâu. Bạn nghĩ là ngồi gõ mỏi tay để đổi **** à.???

b: \(\left\{{}\begin{matrix}3x-2y=4\\2x+y=5\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}3x-2y=4\\4x+2y=10\end{matrix}\right.\)

\(\Leftrightarrow\left\{{}\begin{matrix}-x=-6\\2x+y=5\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=6\\y=5-2x=5-12=-7\end{matrix}\right.\)

 So sánh các số thực sau (không dùng máy tính):

\(\Leftrightarrow\int^{2x-3\sqrt{2}y=\sqrt{2}}_{2x+y\sqrt{2}=-2}\Leftrightarrow\int^{4\sqrt{2}y=-\sqrt{2}\left(\sqrt{2}+1\right)}_{2x=-2-y\sqrt{2}}\Leftrightarrow\int^{y=-\frac{\sqrt{2}+1}{4}}_{2x=-2+\frac{\sqrt{2}\left(\sqrt{2}+1\right)}{4}}\Leftrightarrow\int^{y=-\frac{\sqrt{2}+1}{4}}_{x=\frac{\sqrt{2}-6}{2}}\)

tích cho tui đi

t

\(\left\{{}\begin{matrix}3x+2y=-2\\3x-2y=-3\end{matrix}\right.\\ \Leftrightarrow\left\{{}\begin{matrix}3x+2y=-2\\3x+2y-3x+2y=-2+3\end{matrix}\right.\\ \Leftrightarrow\left\{{}\begin{matrix}3x+2y=-2\\4y=1\end{matrix}\right.\\ \Leftrightarrow\left\{{}\begin{matrix}3x+2.\dfrac{1}{4}=-2\\y=\dfrac{1}{4}\end{matrix}\right.\\ \Leftrightarrow\left\{{}\begin{matrix}x=-\dfrac{5}{6}\\x=\dfrac{1}{4}\end{matrix}\right.\)

\(\left\{{}\begin{matrix}-5x+2y=4\\6x-3y=-7\end{matrix}\right.\\ \Leftrightarrow\left\{{}\begin{matrix}15x-6y=-12\\12x-6y=-14\end{matrix}\right.\\ \Leftrightarrow\left\{{}\begin{matrix}15x-6y=-12\\15x-6y-12x+6y=-12-\left(-14\right)\end{matrix}\right.\\ \Leftrightarrow\left\{{}\begin{matrix}15x-6y=-12\\3x=2\end{matrix}\right.\\ \Leftrightarrow\left\{{}\begin{matrix}15.\dfrac{2}{3}-6y=-12\\x=\dfrac{2}{3}\end{matrix}\right.\\ \Leftrightarrow\left\{{}\begin{matrix}x=\dfrac{2}{3}\\y=\dfrac{11}{3}\end{matrix}\right.\)

\(\Leftrightarrow\left\{{}\begin{matrix}15x-6y=-12\\12x-6y=-14\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}3x=2\\-5x+2y=4\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=\dfrac{2}{3}\\2y-\dfrac{10}{3}=4\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=\dfrac{2}{3}\\y=\dfrac{11}{3}\end{matrix}\right.\)

Ta có: \(\begin{cases}-5x+2y=4\\ 6x-3y=-7\end{cases}\)

=>\(\begin{cases}-30x+12y=24\\ 30x-15y=-35\end{cases}\Rightarrow\begin{cases}-30x+12y+30x-15y=24-35\\ -5x+2y=4\end{cases}\)

=>\(\begin{cases}-3y=-11\\ -5x=-2y+4\end{cases}\Rightarrow\begin{cases}y=\frac{11}{3}\\ -5x=-2\cdot\frac{11}{3}+4=-\frac{22}{3}+4=-\frac{22}{3}+\frac{12}{3}=-\frac{10}{3}\end{cases}\)

=>\(\begin{cases}y=\frac{11}{3}\\ x=\frac{10}{3}:5=\frac23\end{cases}\)