This sign indicates both plus and minus operations. We use it when in equality or inequality equations, root is shifted to other side. for eg. root of 4 = ± 2 because +2 * +2 = 4 and -2 * -2 = 4 . And if we put the minus sign on the up and plus on the bottom then it also correct,..
The Brainliest Answer!
 "±" sign means "plus or minus"we mostly use this when we remove the root
eg √9= ±3.. this mean that the value of square root of 9 is both (-3) and 3 [3*3=9 and (-3)*(-3)=9]
It will not make any difference if we put the minus sign up and plus sign down... but we should do so because this symbol should be written in that way only ±
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