Answer:
a) x=-2 or x=-1
b) x=-1.5
c) (-1.5,-0.25)
Step-by-step explanation:
The given function is
[tex]y = {x}^{2} + 3x + 2[/tex]
We complete the square as follows:
[tex]y = {x}^{2} + 3x + 1.5 ^{2} - {1.5}^{2} + 2[/tex]
[tex]y = {x}^{2} + 3x + 2.25 - 0.25[/tex]
We factor the perfect square;
[tex]y = {(x + 1.5)}^{2} - 0.25[/tex]
We obtained the vertex form of the function.
a) To find the zeros, we set y=0.
[tex] {(x + 1.5)}^{2} - 0.25 = 0[/tex]
[tex] {(x + 1.5)}^{2} = 0.25 [/tex]
[tex]x + 1.5 = \pm \sqrt{0.25} [/tex]
[tex]x = - 1.5 \pm 0.5[/tex]
[tex]x = - 2 \: or \: x = - 1[/tex]
b) The parabola in the form
[tex]y = a( {x - h)}^{2} + k[/tex]
has axis of symmetry at x=h.
Comparing this to
[tex]y = ( {x + 1.5)}^{2} - 0.25[/tex]
We have
[tex]x = - 1.5[/tex]
as the axis of symmetry.
The vertex is (h,k)=(-1.5,-0.25)