Answer:
Step-by-step explanation:
a) the equation representing the parabola is expressed as
h = -16t² - 4t + 20
c) to determine the height after 25 seconds, we would substitute 25 for t into the given equation. It becomes
h = -16(25)² - 4(25) + 20
h = - 10000 - 100 + 20
h = - 10080
d) when the coin lands on the ground, the height would be 0. Therefore,
-16t² - 4t + 20 = 0
Dividing both sides of the equation by 4, it becomes
- 4t² - t + 5 = 0
- 4t² - 5t + 4t + 5 = 0
- t(4t + 5) + 1(4t + 5) = 0
- t + 1 = 0 or 4t + 5 = 0
t = 1 or t = - 5/4
Since t cannot be negative, then t = 1 second
Answer:
C
Step-by-step explanation:
7 5/6 is 7.833333333333333333333
Answer:

Step-by-step explanation:
Area of circle:

By using the area of a circle, we can get the area of a semicircle:

Let's convert the mixed fraction to an improper fraction and then a decimal:
=
= 
Now, we solved for the diameter, to get the radius, we need to divide the diameter by 2:

Now we have the radius, so we can plug in our values and find the area:


All are correct
Explanation:since in none of the answers share the same the same X value and since the graph passes the vertical line test it is a function
The total units of stationery he has would be 55 approximately.
<h3>What is a system of equations?</h3>
A system of equations is two or more equations that can be solved to get a unique solution. the power of the equation must be in one degree.
David keeps a range of stationery in his study.
Let the pencil is represented by x.
Let the erasers be represented by y.
Let the pens be represented by z.
Let n be the stationery.
5/7 of his stationery consists of pencils.
x = 5/7 n
1/6 of the remaining stationery consists of erasers.
y = 1/6 n
There are 20 pens in his study.
z = 20
The total stationery
X + y + z
5/7 n + 1/6 n + 20 = n
20 = n -23/ 36 n
20 = 13 / 36 n
n = 55.38
Therefore, the total units of stationery he has would be 55 approximately.
Learn more about equations here;
brainly.com/question/10413253
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