Question

Which of the following are zeros of f(x) = (x + 2) squared - 1?
*check all that apply*
a. x = -1
b. x = 1
c = -3
d. 3
e. none of the above

Answer 1

f(x)=(x+2)^2-1
f(x)=(x+2)(x+2)-1
f(x)=x^2+4x+4-1
f(x)=x^2+4x+3
-4 +/- radical 4^2-4(1)(3) /2(1)
-4 +/1 radical 16-12 /2
-4 +/ radical 4 /2
(-4+2)/2 = -1
(-4-2)/2= -3

Answer 2

I think I get it... but it's both -1 & -3? you just do both + and -?

Answer 3

It would be both both -3 and -1. The + and - were just there because I used the quadratic equation to solve instead of factoring.

Answer 4

Ahh I see. Thank you very much!

Answer 5

No problem :)