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Ira Lisetskai [31]
2 years ago
14

Sebastian was in a hotel lobby and took the elevator up 7 floors to his room. Then he took the elevator down 9 floors to the par

king garage. He described his movement with the expression 9+ (-7). What is Sebastian's error?
Mathematics
2 answers:
Crank2 years ago
3 0

Answer:

Sebastian didn't interpret the numbers correctly (See explanation)

Step-by-step explanation:

If you go up an elevator, you are gaining floors, so the number is positive.

If you go down an elevator, you are losing floors, so the number is positive.

Looking at the statement, he went 7 floors up to his room, then 9 floors down to the parking garage this can be represented as 7 - 9, since the 7 is positive and the 9 is negative.

Sebastian described the movement as 9 + -7, which is wrong - 9 should be -9 and -7 should be 7.

Hope this helped!

Ronch [10]2 years ago
3 0

Answer:

Step-by-step explanation:

Let the lobby level be the reference point for Seb's movement.

The following describes his motion:  +7 - 9.  This puts him 2 floors below the lobby level.

Seb's "9 + (-7)" is incorrect because it indicates an upward trip, whereas the actual direction was downward.  Similarly, "-7" indicates a downward trip, whereas the action direction was upward.

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<u>Answer:</u>

<u>As the number of copies increases The dimension of images continues to decrease until reaching 0. </u>

<u>Step-by-step explanation:</u>

Remember, that the term dimension refers not to an unlimited/unending length but to a specific measurable length.

Therefore, as both copy machines reduces the dimensions of images that are run through the machines over time the dimensions of images would decrease until reaching 0; Implying that the dimension is so small to be invisible, in a sense becoming 0.

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2 years ago
The most popular mathematician in the world is throwing aparty for all of his friends. As a way to kick things off, they decidet
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Answer:

The no. of possible handshakes takes place are 45.

Step-by-step explanation:

Given : There are 10 people in the party .

To Find: Assuming all 10 people at the party each shake hands with every other person (but not themselves, obviously) exactly once, how many handshakes take place?

Solution:

We are given that there are 10 people in the party

No. of people involved in one handshake = 2

To find the no. of possible handshakes between 10 people we will use combination over here

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Substitute the values in the formula

^{10}C_{2}=\frac{10!}{2!(10-2)!}

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No. of possible handshakes are 45

Hence The no. of possible handshakes takes place are 45.

4 0
2 years ago
Angelique had 20 tokens to use for games at the arcade. She lost some of them. Her dad tripled the tokens she had left. Angeliqu
alexandr402 [8]

Answer:  Both the expressions are exactly same . Both are representing the number of tokens she has now.


Step-by-step explanation:

Given: The total number of tokens Angelique has= 20

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Then, The remaining  tokens she has = 20-t

Then her father triples the tokens she has.

now, the number of token she has=3(20-t)....>Angelique's expression

By using distributive property,

The number of token she has=3\times20-3t

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Hence, both are the same expressions. Both are representing the number of tokens she has now.

7 0
2 years ago
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(b) For those values of k, verify that every member of the family of functions y = A sin(kt) + B cos(kt) is also a solution. y =
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Answer:

Check attachment for complete question

Step-by-step explanation:

Given that,

y=Coskt

We are looking for value of k, that satisfies 4y''=-25y

Let find y' and y''

y=Coskt

y'=-kSinkt

y''=-k²Coskt

Then, applying this 4y'"=-25y

4(-k²Coskt)=-25Coskt

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Divide through by Coskt and we assume Coskt is not equal to zero

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Since k= ± 5/2

y=A•Sin(±5/2t)+ B •Cos(±5/2t)

y'=±5/2ACos(±5/2t)-±5/2BSin(±5/2t)

y''=-25/4ASin(±5/2t)-25/4BCos(±5/2t

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-25A•Sin(±5/2t) - 25B •Cos(±5/2t)

Then, we notice that, 4y'' is equal to -25y, then we can say that y=Coskt is a solution to y=ASinkt+BCoskt

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