Answer:
The roots are the x-intercepts, where the parabola crosses the x-axis. If the parabola opens up and it's vertex is below the x-axis then it crosses the x-axis in two places and has two (real) roots.
Step-by-step explanation:
8*1=8
8-2=6
6*1=6
6-2=4
4*1=4
4-2=2
2*1=2
2-2=0
