Answer:
b = 
Step-by-step explanation:
Given
k =
← multiply both sides by (v - b)
k(v - b) = brt ← distribute left side
kv - kb = brt ( subtract brt from both sides )
kv - kb - brt = 0 ( subtract kv from both sides )
- kb - brt = - kv ( multiply through by - 1 to clear the negatives )
kb + brt = kv ← factor out b from each term on the left
b(k + rt ) = kv ← divide both sides by (k + rt )
b = 
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).
Megan`s plant:
Rate: ( 7 - 4.5 ) / ( 2 - 1 ) = 2.5 in per week
Suzanne`s plant:
Rate: ( 7 - 5 ) / ( 2 - 1 ) = 2 in per week
Answer:
D ) Megan`s at 2.5 inches per week