66 : _ = _R2 what is the answer?

8

Step-by-step explanation:

66 : a = a + 2, anything that has R2 can also be rewritten to be plus 2. Then if you move 2 to the other side it becomes, (66 : a) - 2 = a. Moving a to the other side will create this equation 66 - 2 = a x a. Therefore, 64 = a ^ 2. You just have to find the square root of 64 then.