1). DE II BC What is the value of x?
A

x = 24

Step-by-step explanation:

2(DE) = BC

2(x-12) = x

2x - 24 = x

-2x         -2x

-24 = -x

 -1      -1

24 = x

x = 24

hope this helps

The answer is 120. 
We can tell this because the discriminant is equal to b^2 - 4ac. We know a = -2 (the coefficient of x^2), b = 6 (the coefficient of x) and c = 13 (the number on the end). Then we plug in. 
b^2 - 4ac(6)^2 - 4(-2)(13)36 + 8(13)16 - 104120