Can somebody help me please? My question has been up for a while and I really need help. Thanks!

Two numbers have a sum of -19. one number is x. what expression represents the other number?

Margie is practicing for an upcoming tennis tournament. her first serve is good 20 out of 30 times on average. margie wants to know the estimated probability that her first serve will be good at least four of the next six times she serves. how could she design a simulation for this scenario?

Given that s is the centroid of triangle mno, find sq.