Question

Tính :

\(0-\left(-9\right)\)             \(\left(-8\right)-0\)                  \(\left(-7\right)-\left(-7\right)\)

Answer 1

\(0-\left(-9\right)=9\) \(\left(-8\right)-0=-8\) \(\left(-7\right)-\left(-7\right)=0\)