Question

Which quadratic equation has roots-8 + 3i and -8 - 3i?

Answer 1

The two roots are

$\alpha = -8+3i,~~~ \beta = -8-3i\\\\\\x^2 - (\alpha + \beta)x + \alpha \beta = 0\\\\\implies x^2 - (-8+3i-8-3i)x + (-8+3i)(-8-3i)=0\\\\\implies x^2 +16x + (-8)^2+3^2 =0\\\\\implies x^2 +16x +64+9=0\\\\\implies x^2 +16x +73$

Hence the answer is D.