Pleaseee help im so behind, i also need an explanation for it :(

In the past, professional baseball was played at the astrodome in houston, texas. the astrodome has a maximum height of 63.4 m. the height of a baseball t seconds after it is hit straight up in the air with a velocity of 45 ft/s is given by h = -9.8t2 + 45t + 1. will a baseball hit straight up with this velocity hit the roof of the astrodome? use the discriminant to explain your answer.

Need solving this second acceleration problem.

Find the number of real number solutions for the equation. x2 + 5x + 7 = 0 0 cannot be determined 1 2