\(x^2+x=0\\ x\left(x+1\right)=0 \)

x=0 hoặc x+1 =0

x=0 hoặc x =-1 

Vậy...

Hóng Dzịt tặng coin :))

mình giống tên nhau qué lè 

\(=-\dfrac{5}{7}\left(\dfrac{4}{13}+\dfrac{9}{13}\right)+\left(-\dfrac{2}{7}\right)\\ =-\dfrac{5}{7}.\left(1\right)+\left(-\dfrac{2}{7}\right)=-\dfrac{5}{7}+\left(-\dfrac{2}{7}\right)=-1\)

1A
2-B

3-B

4-C

Hay :)))

10 \(dm^2\)