Define the tectonic plates..??

they are dozens of things that make up the surface of the earth, or something along those lines

➢Tectonic plates are pieces of Earth's crust and uppermost mantle, together referred to as the lithosphere. These are (also called lithospheric plates) massive, irregularly shaped slab of solid rock, generally composed of both continental and oceanic lithosphere.

reflecting point a across the origin negates both of its coordinates.

b = (5, -4)