Answer:
[Vertex form]
Step-by-step explanation:
Given function:
We need to find the vertex form which is.,
where 
represents the co-ordinates of vertex.
We apply completing square method to do so.
We have
First of all we make sure that the leading co-efficient is =1.
In order to make the leading co-efficient is =1, we multiply each term with -3.
Isolating 
and 
terms on one side.
Subtracting both sides by 15.
In order to make the right side a perfect square trinomial, we will take half of the co-efficient of term, square it and add it both sides side.
square of half of the co-efficient of term = 
Adding 36 to both sides.
Since 
is a perfect square of 
, so, we can write as:
Subtracting 21 to both sides:
Dividing both sides by -3.
[Vertex form]
Answer:
A
Step-by-step explanation:
you can just plug in the numbers until they come out equal
Answer:
Step-by-step explanation:
slope :
= 0.5
Maximum can be determined by taking derivative and set it equal to zero.
Answer:
1.07 hours
Step-by-step explanation:
14 miles = 1 hour
15 miles = x hours
Equal these two together
14 mi/1hr = 15 mi/xhr
Cross multiply
14 mi × x hr = 1 hr × 15 mi
I will stop using the units for now so it won't be as confusing
14x = 15
Divide both sides by 14 to isolate the variable
14x ÷ 14 = 15 ÷ 14
x = 1.07... hours
