SOLUTION: If a and b are real numbers and a2 = b2, does a = b? can this be explained to me?

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Question 135723: If a and b are real numbers and a2 = b2, does a = b? can this be explained to me?

Answer by ptaylor(2198) About Me  (Show Source):
You can put this solution on YOUR website!
a%5E2=b%5E2 or
a%5E2-b%5E2=0 and this can be factored
%28a-b%29%28a%2Bb%29=0
a-b=0
a=b
and
a%2Bb=0
a=-b
When we are dealing with squares and square roots, we cannot afford to forget the plus or minus characteristics
-2 does not equal +2 but (-2)^2 does equal (+2)^2
Hope this helps---ptaylor