The graph is missing, so I am using a graph for a similar question.
It migh even be the same question, but the important thing is that I am going to explain you the situation in several sections of this diagram and so you will be able to work this kind of problems by your selfl.
The graph is attached (see the figure).
The graph shows the evolution of the
speed (vertical-axis) over time (horizontal-axis).In the
section A, the speed increases linearly: so the car is
speeding up uniformly (constant acceleration).
In the
section B, the line is horizontal which shows that the speed is constant. That is a
uniform motion.
In the
section C, the speed is decreasing uniformly, so the car is
slowing down with uniform negative acceleration.
So, for this graph, the answer is:
in the setion C. the car is slowing down (uniformly).
I used math
anyway
remember you can do anything to an equation as long as you do it to both sides
so
4n+2 and 1/2=2n+5
minus 2n both sides
4n-2n+2 and 1/2=2n-2n+5
2n+2 and 1/2=0+5
2n+2 and 1/2=5
minus 2 and 1/2 both sides
2n=2 and 1/2
divide both sides by 2
I mean times both sides by 1/2
n=1 and 1/4
answer is C
3 and 4
Step-by-step explanation:
y=5x
y=5(0)
y=0
y=5x
y=5(10)
y=50
y=5x
y=5(51)
y=255
y=5x
y=5(400)
y=2000
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).