Answer:

Step-by-step explanation:
The equation of a parabola in vertex form:

<em>(h, k)</em><em> - vertex</em>
The focus is

We have the vertex (2, -5) and the focus (2, -4).
Calculate the value of <em>a</em> using 
<em>k = -5</em>
<em>add 5 to both sides</em>
<em>multiply both sides by 4</em>


Substitute

to the vertex form of an equation of a parabola:

The standard form:

Convert using


<em>use the distributive property: a(b+c)=ab+ac</em>

Answer:
Price of Caleb's groceries before tax= $6.4
Step-by-step explanation:
Let price of groceries before tax be = $ 
Sales tax % = 2.5%
Sales tax applied = 
Actual sales tax paid = $1.60
∴ 
Multiplying both sides by 100.


Dividing both sides by 25.


∴ Price of groceries before tax= $6.4
Answer:
4k-6
Step-by-step explanation:

Let's assume
It started in 2000
so, t=0 in 2000

we can use formula

we can plug value

In 2005, the same survey was made and the total amount of gamma ray bursts was 7.3 million
so, at t=2005-2000=5
P(t)=7.3 million
we can plug value and then we can solve for r


now, we can plug back

now, we have
P(t)=1 billion =1000 million
so, we can set it and then we can solve for t


approximately

Year is 2000+192
year is 2192................Answer