It’s B.
If I’m wrong them uhh.. my bad?
Answer:
the answer is ac line segment
Vertex form uses the following formula:

Identify the values of h and k in your function:


The vertex is found with the following point:


The vertex will be found at
(-5, -28).
-10 + a = 6a - 7a
Rearrange the left hand side
a - 10 = 6a - 7a
Simplify 6a - 7a
a - 10 = -a
Add a on both sides
2a - 10 = 0
Add 10 on both sides
2a = 10
Divide by 2 on both sides
a = 5
1/6 of 24 = 4
3/7 of 21 = 9
1/3 of 21 = 7