Answer:
i think it is b or d im not for sure though
Step-by-step explanation:
Answer: The ball hits the ground at 5 s
Step-by-step explanation:
The question seems incomplete and there is not enough data. However, we can work with the following function to understand this problem:
(1)
Where 
models the height of the ball in meters and 
the time.
Now, let's find the time when the ball Sara kicked hits the ground (this is when 
):
(2)
Rearranging the equation:
(3)
Dividing both sides of the equation by 
:
(4)
This quadratic equation can be written in the form 
, and can be solved with the following formula:
(5)
Where:
Substituting the known values:
(6)
Solving we have the following result:
This means the ball hit the ground 5 seconds after it was kicked by Sara.
Frank can build a fence in twice the time it would take Sandy. Working together, they can build it in 7 hours. How long will it take each of them to do it alone?
Answer
If Frank and Sandy can build the fence in 7 hours, they must be building
1
7
of the fence every hour.
Now, let the amount of time it takes Sandy be
x
hours so that Frank takes
2
x
hours. Sandy can build
1
x
of the fence every hour and Frank can build
1
2
x
of the fence every hour.
We now have the following equation to solve.
1
x
+
1
2
x
=
1
7
2
+
1
2
x
=
1
7
21
=
2
x
x
=
21
2
=
10.50
Thus, Sandy takes
10.50
hours and Frank takes
21
hours.
Answer:
B
Step-by-step explanation:
Substitute x = h + 2 into f(x), that is
f(h + 2)
= 4(h + 2)² - 17 ← expand factor using FOIL
= 4(h² + 4h + 4) - 17 ← distribute parenthesis and simplify
= 4h² + 16h + 16 - 17
= 4h² + 16h - 1 → B
Answer:
56.52mm
Step-by-step explanation:
