How to add or take from current x y position?

I know that it is likely an extremely simple question, but how would I go about changing the x position of a sprite by say, 5 when I press a key. I have tried position.transform (5,0) but it simply sets the x value to 5 and the y value z…

Position is a Vector3. So you need to add another vector3 to it representing the translation in x/y/z axes.

transform.position += new Vector3(5, 0, 0);

would move it 5 units to the right, say.