1. If the discriminant of a quadratic equation is zero, what do you know about the type and number of roots of the quadratic equation? A. The quadratic equation has one real number root.

B. The quadratic equation has one imaginary and one real number root.

C. The quadratic equation has two imaginary number roots.

D. The quadratic equation has two distinct real number roots.

C

Step-by-step explanation:

a 4/6 = 9/12   not proportional

step-by-step explanation:

to find which are not proportional, we can use cross products

if it is true, they are proportional.   if it is not true, they are not proportional.

a 4/6 = 9/12

4* 12 = 6*9

48 = 54

not this is not proportional  

b 2/3 = 12/18  

2* 18 = 3 * 12

36 = 36

this is proportional

c 5/4 = 10/8  

5*8 = 4*10

40 = 40

this is proportional

d 7/5 = 35/25

7*25 = 5 * 35

175 = 175

is proportional

irrational, cannot