Answer:
(√5)/2
Step-by-step explanation:
To simplify the root, we remove perfect squares.
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Factors that are the same in numerator and denominator cancel. A square under the radical can have its root brought out of the radical.
[tex]\sqrt{\dfrac{405}{324}}=\sqrt{\dfrac{9^2\cdot5}{9^2\cdot2^2}}=\boxed{\dfrac{\sqrt{5}}{2}}[/tex]