1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
musickatia [10]
3 years ago
6

Every year, a car loses 15% of the value it had the year before. If the car's initial value is $ 24,000, then how long will it t

ake for the car to be worth half of its value?
Mathematics
1 answer:
ella [17]3 years ago
8 0

Answer:

4.62 years

Step-by-step explanation:

Half the car's value =>$24,000/2 = $12,000

The formula for exponential decrease =

y = a(1 - r)^t

y = Initial value = $24,000

a = Value after time t = $12,000

r = Decrease rate = 15% = 0.15

t = time in years =??

Hence,

24,000 = 12000 ( 1 - 0.15)^t

Divide both sides by 12000

24000/12000 = 12000 ( 0.85)^t/ 12000

2 = 0.85^t

We take the logarithm of both sides

log 2 = log (0.85)^t

log 2 = t log 0.85

Divide both sides by log 0.85

t = log 2/log 0.85

t = 4.62098120373 years

Approximately = 4.62 years

It would take 4.62 years to be worth half the initial price

You might be interested in
If:<br> JK = 6x + 2,<br> KL=7+4, and<br> JL= 45,<br> Find KL.<br> J<br> K<br> L
ivolga24 [154]

Answer: 25

Step-by-step explanation: got it wrong and got the answer Took 1 for the team

3 0
3 years ago
Need help please help me
Ostrovityanka [42]
The solution is the point of intersection between the two equations.

Assuming you have a graphing calculator or a program to lets you graph equations (I use desmos) you simply put in the equetions and note down the coordinates of the point of intersection.

In the graph the first equation is in blue and the second in red.

The point of intersection = the solution = (-6 , -1)



If you dont have access to a graphing calculator you could draw the graphs by hand;

1) Draw a table of values for each equation; you do this by setting three or four values for x and calculating its image in y (you can use any values of x)

y = 0.5 x + 2 (Im writing 0.5 instead of 1/2 because I find its easier in this format)

x | y
-1 | 1.5 * y = 0.5 (-1) + 2 = 1.5
0 | 2 * y = 0.5 (0) + 2 = 2
1 | 2.5 * y = 0.5 (1) + 2 = 2.5
2 | 3 * y = 0.5 (2) + 2 = 3

y = x + 5

x | y
-1 | 4 * y = (-1) + 5 = 4
0 | 5 * y = (0) + 5 = 5
1 | 6 * y = (1) + 5 = 6
2 | 7 * y = (2) + 5 = 7

2) Plot these point on the graph
I suggest to use diffrent colored points or diffrent kinds of point markers (an x or a dot) to avoid confusion about which point belongs to which graph

3) Using a ruler draw a line connection all the dots of one graph and do the same for the other

4) The point of intersection is the solution

8 0
3 years ago
Read 2 more answers
R^2+8r=-7<br>solve the equation with the quadratic formula showing work
Yuliya22 [10]

Answer:

Step-by-step explanation:

r²+8r=−7

Step 1: Subtract -7 from both sides.

r²+8r−(−7)=−7−(−7)

r²+8r+7=0

Step 2: Use quadratic formula with a=1, b=8, c=7.

r=r=\frac{-b+or-\sqrt{-4ac}  }{2a}

r=\frac{-8+or-\sqrt{(8})^2-4(1)(7) }{2(1)}

7 0
3 years ago
The claim is that the white blood cell counts of adult females are normally​ distributed, with a standard deviation equal to 1.6
maxonik [38]

Answer:

78.46

Step-by-step explanation:

Given that

Pop. Standard deviation = 1.61

Sample standard deviation = 2.15

Sample mean = 7.47

Sample size = 45

Recall that

Test stat for chi square

= (n - 1) (sample standard dev/pop standard dev)^2

= 45 - 1 (2.15/1.61)^2

= 44(1.3354)^2

= 44 × 1.78329

= 78.46

4 0
3 years ago
Read 2 more answers
Factor completely x^8- 16.
Nataly_w [17]

Answer:

Step-by-step explanation:


So in this example we'll be using the difference of squares which essentially states that: (a-b)(a+b)=a^2-b^2 or another way to think of it would be: a-b=(\sqrt{a}-\sqrt{b})(\sqrt{a}+\sqrt{b}). So in this example you'll notice both terms are perfect squares. in fact x^n is a perfect square as long as n is even. This is because if it's even it can be split into two groups evenly for example, in this case we have x^8. so the square root is x^4 because you can split this up into (x * x * x * x) * (x * x * x * x) = x^8. Two groups with equal value multiplying to get x^8, that's what the square root is. So using these we can rewrite the equation as:

x^8-16 = (x^4-4)(x^4+4)

Now in this case you'll notice the degree is still even (it's 4) and the 4 is also a perfect square, and it's a difference of squares in one of the factors, so it can further be rewritten:

x^4-4 = (x^2-2)(x^2+2)

So completely factored form is: (x^2-2)(x^2+4)(x^4+4)

I'm assuming that's considered completely factored but you can technically factor it further. While the identity difference of squares technically only applies to difference of squares, it can also be used on the sum of squares, but you need to use imaginary numbers. Because x^2+4 = x^2-(-4). and in this case a=x^2 and b=-4. So rewriting it as the difference of squares becomes: x^4+4 = x^4 - (-4) = (x^2-\sqrt{-4})(x^2+\sqrt{-4}) = (x^2-2i)(x^2+2i) just something that might be useful in some cases.

7 0
1 year ago
Read 2 more answers
Other questions:
  • How do I draw a model for 63 divided 6
    5·1 answer
  • The United States is not a totally free market economy. Which of these is an example of the government limiting the actions of b
    8·2 answers
  • Tyler has 2 dogs and 7 fish. What is Tyler's ratio of fish to dogs?
    8·2 answers
  • WILL MARK YOU BRAINLIEST NO GUESSES PLZ!!!!!
    8·1 answer
  • You and your friend each collect rocks and fessis your friend collects three times as many roots and half as many fossils as you
    10·1 answer
  • If 3/4 = x/8, then x is equal to
    5·2 answers
  • Alyssa bought a dress for $52 and 3 pairs of jeans. She paid a total of $125. Write an equation to represent this word problem
    7·2 answers
  • Find the area for this problem
    5·1 answer
  • How many 3/4s are in 3 2/4
    10·1 answer
  • A Web music store offers two versions of a popular song. The size of the standard version is 2.1 megabytes (MB). The size of the
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!