How fast do the continents on Earth move?

hmm.. I tried

Explanation:

Earths land masses moves about 0.6 a year

but the continents move away from each other of a rate of about 2.5 centimeters  like (1 inch) per year but while that is happening the Rift valleys are sites where a continental landmass is ripping itself apart.

answer: c.

explanation:

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

: -)