Evaluate: $9+\left(-8\right)$9+(−8)
Evaluate: $-2+\left(-8\right)$−2+(−8)
Evaluate: $3-\left(-9\right)$3−(−9)
Evaluate: $-2-\left(-8\right)$−2−(−8)
Understand addition and subtraction of fractions, decimals, and integers