You can
put this solution on YOUR website!If S is the number of species last year, and the Earth is losing 4,000 species a year, then this year the Earth will have

species. For instance, if S=10,000, then subtract 4,000 to get 6,000. So to generalize, let the number of species be S and subtract 4000 from S.
You can
put this solution on YOUR website!It is estimated that the Earth is

of plants and animals

year.
If

represents the number of species living


, how many species are on Earth this year?


should be:

–