determinant: 
(a) 
D<0 means there are no real roots. there are two complex roots with imaginary components.
(b) D=16+20=36>0
D>0 means there are two real roots
(c) D = 20^2-4*4*25 = 0
D=0 means there is one real root with multiplicity 2
Answer:
A. <em>A </em>and <em>F</em>.
Step-by-step explanation:
By observing the number line given, you can assume that in between -4 and -6 would be the number -5, replaced by the variable <em>A</em>, and the same thing with 4 and 6, where 5 is replaced by <em>F</em>.
I think it's 1.90. I am not fully sure about the answer if it's wrong.