If x = −4 is a zero of the polynomial function f(x) = 2x3 + 13x2 + 23x + 12, which of the following is another zero of f(x)
A. X=4
B. X=-1
C. X= 1
D. X=12
A “zero” is the number x has to be for the equation to equal 0. So, looking at the equation, x HAS to be negative, because the whole equation has +’s, which will never amount to 0 unless X is a negative number.
You can also plug -1 in for X as so: 2(-1)3 + 13(-1)2 + 23(-1) + 12