First, add #color(red)(16)# to each side of the equation to isolate the #x^2# term while keeping the equation balanced:
#4x^2 - 16 + color(red)(16) = 28 + color(red)(16)#
#4x^2 - 0 = 44#
#4x^2 = 44#
Next, divide each side of the equation by #color(red)(4)# to isolate #x^2# while keeping the equation balanced:
#(4x^2)/color(red)(4) = 44/color(red)(4)#
#(color(red)(cancel(color(black)(4)))x^2)/cancel(color(red)(4)) = 11#
#x^2 = 11#
Now, take the square root of each side of the equation to solve for #x# while keeping the equation balanced. Remember, when taking the square root there is a positive and negative solution:
#sqrt(x^2) = +-sqrt(11)#
#x = +-sqrt(11) = +-3.317# rounded to the nearest thousandth.
