The left hand side of the equation is almost a perfect square:

In order for it to be a perfect square: x^2 + 4x + ____ = 2 + ____

To find the number that completes the square take 1/2 of 4 and square it

So 4 gets added to both sides

Then the right side becomes 6

Then we can write the left side like this: (x + 2) ^2

So (x + 2)^2 = 6

then take the sqrt of both sides but do not forget the +/- with the sqrt

Then subtract 2 from both sides:

You will have two answers a plus and a minus and you can check your work by using the quadratic formula 🙂