Which ratios are equal to each other?
a.) 1 : 16 and 2 : 8
b.) 2 : 32 and 4 : 8
c.) 1 : 64 and 4 : 16
d.) 1 : 16 and 4 : 64

What is the value of the discriminant, b2 ? 4ac, for the quadratic equation 0 = x2 ? 4x + 5, and what does it mean about the number of real solutions the equation has?