Answer:
12
Step-by-step explanation:
If a = 6 and b = -6
a + b = 0
(6) + (-6) = 0
6 – 6 = 0
ab = -36
(6)(-6) = -36
6 • -6 = -36
a – b = 12
(6) – (-6) = 12
6 + 6 = 12
I hope this helps
