Explanation:
Use PEMDAS
(8 + 6) : (4 : 2) = 14 : 2 = 7
84 : (6 · 2) = 84 : 12 = 7
8 + (4 - 6) : 2 = 8 + (-2) : 2 = 8 + (-1) = 8 - 1 = 7
8 - (6 - 4) : 2 = 8 - 2 : 2 = 8 - 1 = 7
8 - (6 - 2) : 4 = 8 - 4 : 4 = 8 - 1 = 7
8 + (2 - 6) : 4 = 8 + (-4) : 4 = 8 + (-1) = 8 - 1 = 7
8 - 2 : (6 - 4) = 8 - 2 : 2 = 8 - 1 = 7
8 + 2 : (4 - 6) = 8 + 2 : (-2) = 8 + (-1) = 8 - 1 = 7
8 - 4 : (6 - 2) = 8 - 4 : 4 = 8 - 1 = 7
8 + 4 : (2 - 6) = 8 + 4 : (-4) = 8 + (-1) = 8 - 1 = 7