15 points help plz

Aquadratic equation in standard from is written ax^2= bx+c, where a,b and c are real numbers and a is not zero?

Two friends are reading books. jimmy reads a book with 21,356 words. his friend bob reads a book with one-and-a-half times as many words. which expression represents the number of words bob reads?

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 −