Which is the best way to solve the equation x^2 = n?

  see below

Step-by-step explanation:

You solve an equation by undoing what is done to the variable. When the variable is squared, as here, you undo the squaring by taking the square root. Any operation you do on one side of the equation must also be done on the other side. Hence, you take the square root of both sides of the equation.

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