Question

The polynomial equation x3+x2=-9x-9 has complex roots +-3i . What is the other root? Use a graphing calculator and a system of equations.

–9
–1
0
1

Answer 1

It's B. on EtDtGte

Explanation:

Answer 2

If the equation has roots of +-3i. The equation would be,
(x + 3i)(x - 3i)
which is equal to x^2 - (3i)^2 = x^2 + 3.
Using division either by synthetic or long method,
(x^3 + x^2 + 9x + 9)/(x^2 + 3)
is equal to,
x + 1 or x = -1
Thus, the answer is the second choice.