Answer:
-9
Step-by-step explanation:
This what you wrote:
[tex] cd - \dfrac{d^2}{4} = [/tex]
[tex] = (0)(-6) - \dfrac{(-6)^2}{4} [/tex]
[tex] = 0 - \dfrac{36}{4} [/tex]
[tex] = -\dfrac{36}{4} [/tex]
[tex] = -9 [/tex]
Maybe this is what you meant to write:
[tex] \dfrac{cd - d^2}{4} = [/tex]
[tex] = \dfrac{(0)(-6) - (-6)^2}{4} [/tex]
[tex] = \dfrac{-36}{4} [/tex]
[tex] = -9 [/tex]