How to solve $a^2=b^2$?
Should I consider if the number is negative or positive?
$\endgroup$ 23 Answers
$\begingroup$$$a^2=b^2\implies a=\pm b$$ so they are either the same sign (or zero) or different sign ...
$\endgroup$ $\begingroup$The equation is equivalent to $a^2-b^2 = 0$ or $(a-b)(a+b) = 0$, hence all $a,b\in\mathbb R$ with $b=a$ or $b = -a$ are solutions.
$\endgroup$ $\begingroup$$$ a^2=b^2\Leftrightarrow |a|=|b| $$ $$ \Rightarrow a=b ~~~~~ \vee~~~~~ a=-b$$
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