Using the given zero to find the remaining zeros of the function f(x)=x^3-4^2+49x-196; zero: -7i

Because has real coefficients, you know the complex root occurs along with its conjugate. That is, both are roots to .

This means that dividing through by both factors yields another polynomial with no remainder:



This means the last root (there are only three according to the fundamental theorem of algebra) is .