Respuesta :
The equation that could represent the graph of the parabola is (d) [tex]y = 2x^2 + 8x + 8[/tex]
From the question, we have the following highlights
- The parabola opens up
- The vertex is on the x-axis
The highlights above mean that: the y-coordinate (k) of the vertex is positive.
For a parabola: [tex]y = ax^2 + bx + c[/tex], the vertex is:
[tex](h,k) = (-\frac{b}{2a},f(h))[/tex]
Next, we test the options
(a) y = 9x2 + 6x + 4
We have:
[tex]h = -\frac{6}{2 \times 9}[/tex]
[tex]h = -\frac{1}{3}[/tex]
Substitute -1/3 for x in the function
[tex]y = 9x^2 + 6x + 4[/tex]
[tex]k = 9(1/3)^2 + 6(1/3) + 4[/tex]
[tex]k = 7[/tex]
The value of k is not zero.
So, this cannot represent the parabola
(b) y = 6x2 – 12x – 6
We have:
[tex]h = -\frac{-12}{2\times 6}[/tex]
[tex]h = 1[/tex]
Substitute 1 for x in the function
[tex]y = 6x^2 - 12x - 6[/tex]
[tex]k = 6(1)^2 - 12(1) - 6[/tex]
[tex]k = -12[/tex]
The value of k is not zero.
So, this cannot represent the parabola
(c) y = 3x2 + 7x + 5
We have:
[tex]h = -\frac{7}{2\times 3}[/tex]
[tex]h = -\frac{7}{6}[/tex]
Substitute -7/6 for x in the function
[tex]y = 3x^2 + 7x + 5[/tex]
[tex]k = 3(-7/6)^2 + 7(-7/6) + 5[/tex]
[tex]k = 0.92[/tex]
The value of k is not zero.
So, this cannot represent the parabola
(b) y = 2x2 + 8x + 8
We have:
[tex]h = -\frac{8}{2\times 2}[/tex]
[tex]h = -2[/tex]
Substitute -2 for x in the function
[tex]y = 2x^2 + 8x + 8[/tex]
[tex]k = 2(-2)^2 + 8(-2) + 8[/tex]
[tex]k = 0[/tex]
The y-coordinate (k) is zero.
Hence, [tex]y = 2x^2 + 8x + 8[/tex] could represent the parabola
Read more about parabola at:
https://brainly.com/question/17987697