If discriminant is greater than 0 it has 2 solutions. If it equals 0 it has 1 solution and if its lower than 0 it doesnt has solutions.
0 has 1 solution, -36 no solutions, 3 has 2 solutions p, 2 has two solutions,
100 has 2 solutions, and -4 has no solutions. Hope i helped. If you didnt understand something just tell me