# Complex Roots

Algebra Level 2

Let $$a+bi$$ and $$c+di$$ be the two roots of the quadratic equation $ix^2+(6-7i)x-21-9i=0,$ where $$a<c$$. What is the value of $$ad+bc?$$

$$i$$ is the imaginary number that satisfies $$i^2 = -1.$$

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