Suppose the probability of an event occurring is p(a), and the probability of the event not occurring is p(a’). if p(a)= x and p(a’)= y, which of the following equations must be true

The correct answer is A) t = 1-s.

The probability of the complement of an event is the probability of the event subtracted from 1; in other words

P(A') = 1 - P(A)

Since P(A') = t and P(A) = s,  

t = 1-s

1. a^4+8a^3+24a^2+32a+16

2.y^8+8y^7+28y^6+56y^5+70y^4+56y^3+28y^2+8y+1

3.x^6-3x^4y^2+3x^2y^4-y^6

answer is 17