Ask question

Ask question

All categories

3 years ago

9

Need help with this!!! Only have a few minutes left!!!

1 answer:

Sliva [168]3 years ago

7 0

Answer:

Step-by-step explanation:

You might be interested in

Which expression represents: twice a number increased by 39

Cerrena [4.2K]

Answer:

2x+39

Step-by-step explanation:

8 0

3 years ago

Divide 7/24 by 35/48 and reduce the quotient to the lowest fraction

Ahat [919]

Well, an easier way than to divide fractions is to multiply the fractions, but to do that, flip the numerator and denominator for the second fraction.
For example, it becomes: 7 48 2
-------- × -------- = --------- (top×top & bottom×bottom)
24 35 5

Answer is: 2/5

5 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

3 years ago

Please Help URGENT!!

AlekseyPX

Y + 79 + 37 = 180
y + 116 = 180
y = 64

3 0

3 years ago

Read 2 more answers

When solving this equation: -16 + x = -15 we start with adding 16 to both sides. Why do we use addition?

Ierofanga [76]

Answer:

So you can cancel out the 16. See, the -16 is negative, and if we add +16 to it, then it cancels out and is 0. That way, you have x=1.

Step-by-step explanation:

-16x+x=-15

+16x +16

0+x=1

x=1

6 0

3 years ago