Posted by Jill on .
Write a quadratic equation with real coefficients if one of the solutions is 5 + 7i

math 
Reiny,
complex roots always come in pairs, so the other root is 5  7i
sum of roots = (5+7i) + (57i) = 10
product of roots = (5+7i)(57i)
= 25  49i^2 = 25+49 = 74
equation:
x^2 + 10x + 74 = 0