Question

He roots of x2 − ( ) + 34 are 5 ± 3i.

Answer 1

Use the quadratic formula, x=$\frac{-b+ \sqrt{ b^{2}-4ac} }{2a}$
(don't know how to type the "-"sign in the formula, so there is only the "+" in the formula)
in this case, a=1, c=34, b is unknown
from the roots, we can tell that -b+$\sqrt{b^{2}-4ac }$ =2(5+3i)=10+6i

Note: the original equation already give b as -b, so -(-b)=10, b=10
using b^2-4ac=(6I)^2,
b^2-4*34=-36
b^2=100
you will also get b=10