\(\Leftrightarrow\hept{\begin{cases}3\left(x^2+y^2\right)=10xy\left(1\right)\\x< y< 0\end{cases}}\)  \(\Rightarrow\hept{\begin{cases}xy>0\\x-y>0\\x+y< 0\end{cases}}\)  \(\Rightarrow P< 0\)(*)

\(\left(1\right)\Rightarrow\hept{\begin{cases}3\left(x-y\right)^2=4xy\left(2\right)\\3\left(x+y\right)^2=16xy\left(3\right)\end{cases}}\)

\(\frac{\left(1\right)}{\left(2\right)}=\frac{\left(x-y\right)^2}{\left(x+y\right)^2}=\frac{1}{4}\Rightarrow\orbr{\begin{cases}\frac{x-y}{x+y}=\frac{1}{2}\\\frac{x-y}{x+y}=-\frac{1}{2}\end{cases}}\)

Từ (*)=> P=-1/2

6:6=1

45:9=5

6 : 6 = 1

45 : 9 = 5

tk mk nha bạn, mk nhanh nhất

999-999=0

11111 - 1111 + 10000 

= 10000 + 10000

= 20000

1+1=2.

Tk cho mình đi!Cảm ơn bạn nhiều!

23*45+45*77=45*(23+77)=45*100=4500

35*67+67*65=67*(35+65)=6700