In sean's fish tank there are six times as many goldfish as guppies. there are a total of 21 fish in the tank. how many more goldfish are there then guppies?

Write an explicit formula that represents the sequence defined by the following recursive formula:

State one method by which you can recognize a perfect square trinomial.

Mariah is randomly choosing three books to read from the following: 5 mysteries, 7 biographies, and 8 science fiction novels. which of these statements are true? check all that apply. there are 20c3 possible ways to choose three books to read. there are 5c3 possible ways to choose three mysteries to read. there are 15c3 possible ways to choose three books that are not all mysteries. the probability that mariah will choose 3 mysteries can be expressed as . the probability that mariah will not choose all mysteries can be expressed as 1 −