Because this equation has no #x# term we can solve directly for #x^2#. First, add #color(red)(5)# to each side of the equation to isolate the #x^2# ter while keeping the equation balanced:
#x^2 - 5 + color(red)(5) = 73 + color(red)(5)#
#x^2 - 0 = 78#
#x^2 = 78#
Now, take the square root of each side of the equation to solve for #x# while keeping the equation balanced. Also remember, the square root of a number will have both a negative and positive answer:
#sqrt(x^2) = +-sqrt(78)#
#x = +-sqrt(78) = +-8.832# rounded to the nearest thousandth.