dat (x^2-2x)=a;|2y-1|=b=>pttt \begin{cases}5a-2b=-9 \\ 4a+3b=2 \end{cases} <=>\begin{cases}a=\frac{-7}{9}\\ b= \frac{23}{9}\end{cases} sau do cac ban thay vao tim xva y
dat (x^2-2x)=a;|2y-1|=b=>pttt \begin{cases}5a-2b=-9 \\ 4a+3b=2 \end{cases} <=>\begin{cases}a=\frac{-7}{9}\\ b= \frac{23}{9}\end{cases} sau do cac ban thay vao tim x va y