Answer:
Graph B has 1 real root
Graph A has a negative discriminant
Graph C has an equation with a=1, b=4 , c=-2
Step-by-step explanation:
If we look at the graph, Graph A never crosses the x axis, so it does not have any real roots.
Graph B touches the x axis, but does not cross so it has 1 real root
Graph C crosses the x axis 2 times, so it has 2 real roots.
We know from the discriminant b^2-4ac
If the discriminant >0 it has 2 real roots, so Graph C has a positive discriminant
If the discriminant =0 it has 1 real root, so Graph B has a zero discriminant
If the discriminant <0 it has 0 real roots, so Graph A has a negative discriminant
If we have a=1, b=4 , c=-2
b^2-4ac = 4^2-4(1)(-2) = 16+8 = 24 >0 This must be Graph C
