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Phạm Nhật

3 năm trước

x-2/2=y-3/5=z-5/6vaf x+y-z=12

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thutrangdoan289

3 năm trước

Đáp án:

$\left\{ \begin{array}{l} x = \frac{{50}}{{13}}\\ y = \frac{{99}}{{13}}\\ z = \frac{{137}}{{13}} \end{array} \right.$

Giải thích các bước giải: $\begin{array}{l} \frac{{x - 2}}{2} = \frac{{y - 3}}{5} = \frac{{z - 5}}{6}\\ x + y - z = 12\\ Ap\,\,dung\,\,tinh\,\,chat\,\,cua\,\,\,day\,\,ti\,\,so\,\,bang\,\,nhau\,\,ta\,\,co:\\ \frac{{x - 2}}{2} = \frac{{y - 3}}{5} = \frac{{z - 5}}{6} = \frac{{x - 2 + y - 3 - z + 5}}{{2 + 5 + 6}}\\ = \frac{{x + y - z}}{{13}} = \frac{{12}}{{13}}.\\ \Rightarrow \left\{ \begin{array}{l} x - 2 = \frac{{12}}{{13}}.2\\ y - 3 = \frac{{12}}{{13}}.5\\ z - 5 = \frac{{12}}{{13}}.6 \end{array} \right. \Leftrightarrow \left\{ \begin{array}{l} x = \frac{{50}}{{13}}\\ y = \frac{{99}}{{13}}\\ z = \frac{{137}}{{13}} \end{array} \right.. \end{array}$

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