Answer:
6.64 seconds
Step-by-step explanation:
Given that:
Distance between roof of the terminal and ground = 709 feet
A bucket was dropped from the roof.
To find:
The time taken by the bucket to hit the ground?
Solution:
Distance traveled, 
= 709 feet
Initial velocity of the bucket, 
= 0 feet/sec (because initially it was at rest)
Acceleration of the bucket will be equal to acceleration due to gravity i.e.
or 32.1741 
Let the time taken is 
seconds.
Formula for distance is given as:
Putting all the values:
<span> we have that
standard form of equation for parabola:
(x-h)^2=-4p(y-k)
(h,k) --------->being the (x,y) coordinates of the vertex.
Parabola opens downwards because focus is below vertex on the axis of symmetry.
For given problem:
</span><span>vertex: (-3,2)
axis of symmetry: x=-3
p=distance from vertex to focus on the axis of symmetry=2-(-1)=3
4p=12
Directrix: y=2+p=5
Equation:
(x+3)^2=-12(y-2)
the answer is </span>(x+3)^2=-12(y-2)
Well, we could try adding up odd numbers, and look to see when we reach 400. But I'm hoping to find an easier way.
First of all ... I'm not sure this will help, but let's stop and notice it anyway ...
An odd number of odd numbers (like 1, 3, 5) add up to an odd number, but
an even number of odd numbers (like 1,3,5,7) add up to an even number.
So if the sum is going to be exactly 400, then there will have to be an even
number of items in the set.
Now, let's put down an even number of odd numbers to work with,and see
what we can notice about them:
1, 3, 5, 7, 9, 11, 13, 15 .
Number of items in the set . . . 8
Sum of all the items in the set . . . 64
Hmmm. That's interesting. 64 happens to be the square of 8 .
Do you think that might be all there is to it ?
Let's check it out:
Even-numbered lists of odd numbers:
1, 3 Items = 2, Sum = 4
1, 3, 5, 7 Items = 4, Sum = 16
1, 3, 5, 7, 9, 11 Items = 6, Sum = 36
1, 3, 5, 7, 9, 11, 13, 15 . . Items = 8, Sum = 64 .
Amazing ! The sum is always the square of the number of items in the set !
For a sum of 400 ... which just happens to be the square of 20,
we just need the <em><u>first 20 consecutive odd numbers</u></em>.
I slogged through it on my calculator, and it's true.
I never knew this before. It seems to be something valuable
to keep in my tool-box (and cherish always).
Answer:
x = - 9, x = - 4
Step-by-step explanation:
Set (x +)(x + 9) equal to zero, that is
(x + 4)(x + 9) = 0
Equate each factor to zero and solve for x
x + 4 = 0 ⇒ x = - 4
x + 9 = 0 ⇒ x = - 9
Thus
x = - 9, x = - 4
Answer:
Step-by-step explanation:
130+5x=180
130-130+5x=180-130
5x=50
x=10
