Every number has two (2) square roots. 49/4 is a positive ratio of two square numbers, so the square roots are the positive and negative ratio of the roots of those square numbers.
±√(49/4) = ±(√49)/(√4) = ±7/2
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<em>Comment on math symbols</em>
The square root symbol (√) is generally interpreted to mean the positive, or principal square root. That is why we put the plus/minus (±) symbol in front of it when we're talking about both square roots.
