First, add color(red)(33) to each side of the equation to isolate the x term while keeping the equation balanced:
3x^2 - 33 + color(red)(33) = 0 + color(red)(33)
3x^2 - 0 = 33
3x^2 = 33
Next, divide each side of the equation by color(red)(3) to isolate the x^2 while keeping the equation balanced:
(3x^2)/color(red)(3) = 33/color(red)(3)
(color(red)(cancel(color(black)(3)))x^2)/cancel(color(red)(3)) = 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, the square root of a number produces a positive and negative result:
sqrt(x^2) = +-sqrt(11)
x = +-sqrt(11)
Or
x = +-3.317 rounded to the nearest thousandth.