Three roots of the polynomial equation x^4 - 4x^3 - 2x^2 + 12x + 9 = 0 are 3, -1, and -1. Explain why the forth root must be a real number. Find the forth root.

Hello,

This polynomial function has maximum 4 roots as the degree is 4

and their coefficients are all reals so if one root is a complex number, its conjugate is a root too.

As we know already 3 roots and none of them is a complex number, the fourth one is a real number

And their product is 9 = 3 * 1 * (-1) * (-3) as

(The constant term is 9, the product of the roots)

so the last root is -3

Thanks

step-by-step explanation:

5×5×5+2(8)÷2(2)+3(3)

15+16÷4+9

31÷13

do 31÷13 and u will get ur answer

(2,20) means that the 2 is 2 hours and 20 is 20$. so there both 20$ for 2 hours only the same price. like it says. so, the dunk tank and the bounce house are the same price (20$) for the same amount of time (2 hours).

hope i