Question

Can you see if im right?

Answer 1

The first is incorrect. You can indeed take the roots of both 64 and 4, not just 4.

Answer 2

we should not take your test for you

Answer 3

8^2 = 64, therefore sqrt(64) = 8.

Answer 4

Is it a test?

Answer 5

You're not. I'm asking if I'm right. And no, my practice before the test.

Answer 6

5 is irrational..

Answer 7

the first is correct

Answer 8

root of prime is irational

Answer 9

5 is not irrational, 5 is prime, and thus sqrt(5) is irrational

Answer 10

1 & 2 are correct
3 is incorrect

Answer 11

:o

Answer 12

the sqr of 5 is

Answer 13

why is 3 wrong :D

Answer 14

D: *

Answer 15

Oh awks, there's an a and b, I didn't see that sorry.

Answer 16

Do you know the formula for compound interest?
The formula for depreciation is similar.

Answer 17

No D:

Answer 18

oh, wait is it A

Answer 19

Depreciation formula:

\(F = P(1 - r)^t\)

where F = future value
P = present value
r = rate of depreciation expressed as a decimal
t = number of years

Answer 20

What was the rate of depreciation?

Answer 21

That's the thing, I couldn't find the rate :(

Answer 22

You can calculate it.
The rate of depreciation is constant according to the problem.
That means, the percent depreciation from new to year 1 is the same as the rate of depreciation from year 1 to year 2.
Ok so far?

Answer 23

yea

Answer 24

Since the rate of depreciation is constant, all you need to do is find the percent change in value from year 1 to new or from year 2 to year 1. Once again, you only need to do one of these calculations since the rate of depreciation is constant.

Answer 25

Do you remember how to calculate percent change?

Answer 26

Divide?

Answer 27

Of course, being math, there's a formula for that too:

\( percent~change = \dfrac{new~value - old~value}{old~value} \times 100 \)

Answer 28

Let's use the year 1 value and the new value.

Then
new value = $47,158.35
old value = $54,205

With the formula above and these values you can calculate percent change. This is the same as the depreciation rate.

Answer 29

-13% ?

Answer 30

Is it B :D

Answer 31

Great. The percent change was -13%, or a depreciation rate of 13% per year.
13% = 0.13
Now use the formula for depreciation with the original cost as present value, and 0.13 as r.
Leave t as t.
What do you get?

Answer 32

Well the principle is the beginning value, the rate is -13 and t is years, why i think its B

Answer 33

Don't use -13%. Use 13%. The formula is made for depreciation, so you need to use the depreciation as a positive amount. 13% as a decimal is 0.13

Answer 34

ok, so am i right? ... possibly >.>

Answer 35

No.
Start with the formula. Replace r with 0.13.
What is 1 - 0.13?

\(F = P(\color{red}{1 - r})^t\)

\(\color{red}{1 - 0.13 = 0.87}\)

P = 54,205

Answer 36

So its was D -facepalm-

Answer 37

Write 0.87 in for 1 - r.
Write 54,205 in for P
Leave t as t.
Which choice is it?

Answer 38

Correct. You got it.

Answer 39

haha ty! can you look at this one too?

Answer 40

I'm helping someone with another problem. I'll be here soon.

Answer 41

k

Answer 42

U_U

Answer 43

Sorry. It took me longer than I thought.

Answer 44

no worries,

Answer 45

typo

Answer 46

You chose choice 4.
That means add equation 1 of system 2 to 3 times equation 2 of system 2.

Answer 47

2 and 3 have the same result

Answer 48

Let's look at it.

System 2:
4x - 5y = 2
3x - 8y = 4

What is 3 times equation 2?

Answer 49

9x -24y = 12

Answer 50

good

Here is eq 1 and 3 times eq 2:

4x - 5y = 2
9x - 24y = 12

Now we add them:

13x - 29y = 14

That is not the second equation of system 3, so choice 4 can't be the answer.

Answer 51

so its B? wio says its right?

Answer 52

Now let's look at choice 2.
It also states that system 2 and 3 are the same, but with a different reason.

Answer 53

Let's take the first equation of system 2:

4x - 5y = 2

Now let's take 2 times the second equation of system 2:

6x - 16y = 8

Now add the two equations together.
What do you get?

Answer 54

12x -32y = 16

Answer 55

i have to get off its 2 33 am for me D:

Answer 56

what should i do :(

Answer 57

No.
I already multiplied the second eq by 2, all you need to do is add them together.
Don't multiply the second eq by 2.

Answer 58

4x - 5y = 2
6x - 16y = 8

Add the two eqs above.

Answer 59

10x -21y = 10

Answer 60

oh it was b O_O

Answer 61

Right. That is what is in choice 2.

Answer 62

thank you!!!!!

Answer 63

wlcm