Answer:
Step-by-step explanation:
Use PEMDAS:
P Parentheses first
E Exponents
MD Multiplication and Division
AS Addition and Subtraction
[tex]6:(-3)-(-9)[/tex] first - division
[tex]=-2+9[/tex] use commutative property a + b = b + a
[tex]=9+(-2)=9-2=7[/tex]