x > 3
There's not way to explain a step by step, for this type of inequality at least. However, I was always told to look at the signs as an alligator mouth growing up. The alligator will want to eat the larger number; so you'll write/draw with its 'mouth' open towards the larger. In this case, it says x is greater than three, so the 'alligator' will want to eat the x since it's larger.
