Just use the order of operations to do out the problem.
-2(15/-5)-6/2+9
you start with executing any parenthesis
-2(-3)-6/2+9
You then do exponents. but their are none.
-2(-3)-6/2+9
You then do multiplication and division. starting from left to right. (multiplication and division are "equal" in the order of operations)
-2(-3) = -6 <<< Incorrect -2(-3) = (+)6
-6/2 = -3
plug in those values...
-6-3+9
You then do addition and subtraction at the same time. starting from left to right. (same deal here as above)
I will leave the last step to you
A shortcut to remember order of operations is PEMDAS
P
arentheses 1
E:exponents 2
M:multiplication 3
D:division 3
A:addition 4
S: subtraction 4
The numbers represent in what order to use the operations
Knight