What is the discriminant of the quadratic equation 0 = –x2 + 4x – 2?

What are the solutions of the system? solve by graphing. y = -x^2 -6x - 7 y = 2

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?

Andy has $310 in his account. each week, w, he withdraws $30 for his expenses. which expression could be used if he wanted to find out how much money he had left after 8 weeks?