Ask question

Ask question

All categories

3 years ago

11

Eric has rock and classical CDs in his car. The number of rock CDs is 3 more than the number of classical CDs. Let c represent t

he number of classical CDs. Write an expression for the number of rock CDs.

2 answers:

Lubov Fominskaja [6]3 years ago

6 0

Answer:

Number of rock CDs = (C+3)

Step-by-step explanation:

Eric has rock and classical CDs in his car.

Let the number of classical CDs = c

Since Eric has rock CDs, which are 3 more than the number of classical CDs.

So expression to show this will be

Number of rock CDs = (C+3)

zimovet [89]3 years ago

3 0

3 times C like this. 3xC

You might be interested in

A water tank that holds 500 gallons leaks LaTeX: \frac{1}{2}1 2 gallon of water every hour. What is the rate of change for the f

Paul [167]

Answer:

250

Step-by-step explanation:

4 0

3 years ago

Oil is pumped continuously from a well at a rate proportional to the amount of oil left in the well. Initially there were millio

JulijaS [17]

Answer:

The amount of oil was decreasing at 69300 barrels, yearly

Step-by-step explanation:

Given

$Initial =1\ million$

$6\ years\ later = 500,000$

Required

At what rate did oil decrease when 600000 barrels remain

To do this, we make use of the following notations

t = Time

A = Amount left in the well

So:

$\frac{dA}{dt} = kA$

Where k represents the constant of proportionality

$\frac{dA}{dt} = kA$

Multiply both sides by dt/A

$\frac{dA}{dt} * \frac{dt}{A} = kA * \frac{dt}{A}$

$\frac{dA}{A} = k\ dt$

Integrate both sides

$\int\ {\frac{dA}{A} = \int\ {k\ dt}$

$ln\ A = kt + lnC$

Make A, the subject

$A = Ce^{kt}$

$t = 0\ when\ A =1\ million$ i.e. At initial

So, we have:

$A = Ce^{kt}$

$1000000 = Ce^{k*0}$

$1000000 = Ce^{0}$

$1000000 = C*1$

$1000000 = C$

$C =1000000$

Substitute $C =1000000$ in $A = Ce^{kt}$

$A = 1000000e^{kt}$

To solve for k;

$6\ years\ later = 500,000$

i.e.

$t = 6\ A = 500000$

So:

$500000= 1000000e^{k*6}$

Divide both sides by 1000000

$0.5= e^{k*6}$

Take natural logarithm (ln) of both sides

$ln(0.5) = ln(e^{k*6})$

$ln(0.5) = k*6$

Solve for k

$k = \frac{ln(0.5)}{6}$

$k = \frac{-0.693}{6}$

$k = -0.1155$

Recall that:

$\frac{dA}{dt} = kA$

Where

$\frac{dA}{dt}$ = Rate

So, when

$A = 600000$

The rate is:

$\frac{dA}{dt} = -0.1155 * 600000$

$\frac{dA}{dt} = -69300$

<em>Hence, the amount of oil was decreasing at 69300 barrels, yearly</em>

7 0

2 years ago

Y=f(x) = (1/2)<br> Find f(x) when x = 1

sammy [17]

The value of function on x=1 is 0.5

Step-by-step explanation:

In order to find the value of a function on given input, the input is put at the place of variable in the function.

Given function is:

$f(x) = (\frac{1}{2})^x$

We have to find the value of function on x = 1

Putting x = 1 in function

$f(1) = (\frac{1}{2})^1\\= \frac{1}{2}\\= 0.5$

Hence,

The value of function on x=1 is 0.5

Keywords: Functions variables

Learn more about functions at:

LearnwithBrainly

7 0

3 years ago

Help please I'm need help with number 4, 5 , and 6

Westkost [7]

4= 121 5= 49 6= 169 hope this helps

4 0

3 years ago

Read 2 more answers

Simplify. a−(b+c) PLEEEASE HELP!!!!!!!!

katrin2010 [14]

a-b-c

that's the answer the negative sign affects what's in the bracket

6 0

3 years ago

Read 2 more answers