Algebra: Define the value of X: 6x - 2 + 2x = -2 + 4x + 8?

Questions

Anthropoid (ape) of equatorial Africa that, physically & genetically, is the animal most closely related to humans?

Any animal lacking a vertebral column, or backbone?

Any comparatively small body of land completely surrounded by water?

Any free-moving liquid in outer space will form itself into a sphere, because of it's surface ______?

Any material that hardens & becomes strongly adhesive after application in plastic form?