Answer:
When you graph the quadratic equation, you have three possibilities...
1. The graph touches x-axis once. Then that quadratic equation only has one solution and you find it by finding the x-intercept.
2. The graph touches x-axis twice. Then that quadratic equation has two solutions and you also find it by finding the x-intercept
3. The graph doesn't touch the x-axis at all. Then that quadratic equation has no solutions. If you really want to find the solutions, you'll have to go to imaginary solutions, where the solutions include negative square roots.