Which statement is true?

Let s(t) be the amount of salt in the tank at time t. Then s(0) = 50 lb.

Salt flows into the tank at a rate of

(2 gal/min) (6 lb/gal) = 12 lb/min

and flows out at a rate of

(2 gal/min) (s(t)/300 lb/gal) = s(t)/150 lb/min

so that the net rate at which salt is exchanged through the tank is

ds(t)/dt = 12 - s(t)/150 … (lb/min)

Solve for s(t). The DE is separable, so we have

ds/dt = 12 - s/150

150 ds/dt = 1800 - s

150/(1800 - s) ds = dt

Integrate both sides to get

-150 ln|1800 - s| = t + C

Solve for s :

ln|1800 - s| = -t/150 + C

1800 - s = exp(-t/150 + C )

1800 - s = C exp(-t/150)

s = 1800 - C exp(-t/150)

Now given that s(0) = 50, we solve for C :

50 = 1800 - C exp(-0/150)

50 = 1800 - C

C = 1750

Then the amount of salt in the tank at any time t ≥ 0 is

s(t) = 1800 - 1750 exp(-t/150)

To find the time it takes for the tank to hold 100 lb of salt, solve for t in

100 = 1800 - 1750 exp(-t/150)

1700 = 1750 exp(-t/150)

34/35 = exp(-t/150)

ln(34/35) = -t/150

t = -150 ln(34/35) ≈ 4.348

So it would take approximately 4.348 minutes.

By the way, we didn't have to solve for s(t), we could have instead stopped with

-150 ln|1800 - s| = t + C

Solve for C - this C is not the same as the one we found using the other method. s(0) = 50, so

-150 ln|1800 - 50| = 0 + C

C = -150 ln|1750|

==>   t = 150 ln(1750) - 150 ln|1800 - s|

Then s(t) = 100 lb when

t = 150 ln(1750) - 150 ln(1700)

t = 150 ln(1750/1700)

t = 150 ln(35/34)

t ≈ 4.348

Answer:

Step-by-step explanation:

We know that the thickness of the lake decreases at a rate of 0.2 meters per week, so we can write:

S(t)=-0.2t+4

we also know that after 7 weeks, the sheet is only 2.42 meters thick, which means we can write:

S(7)=2.42

S(7)=-0.2*7+X

S(7)=-1.4+X

2.42=-1.4+X

X=3.82

So, the function is: S(t)=--0.2*t+3.82

Answer:

y = 3.8 - 0.2x

Step-by-step explanation:

Khan Academy

Answer:

The relation between individual and society is very close. Essentially, “society” is the regularities, customs and ground rules of antihuman behavior. ... Man is biologically and psychologically equipped to live in groups, in society. Society has become an essential condition for human life to arise and to continue.

Answer:

x2 - 16x + 28 = (x - 2)(x - 14)

Step-by-step explanation:

Even though you don't mention any factors below, it is easy to tell that the above-given two factors must be the ones you are looking for.

Answer:

shift the graph up 1 unit

Step-by-step explanation:

d is the vertical shift

+1 means we shift the graph up 1 unit

Answer:

Arc KN = 201°

Step-by-step explanation:

Recall: According to the tangent-secant exterior angle theorem, the measure of the vertex angle formed at an external point where a tangent and a secant meet outside a circle is ½ of the difference between the intercepted major and minor arcs.

Applying this to the problem given, we have:

m<L = ½(Arc KN - Arc KM)

m<L = 70° (given)

Arc KN = ?

Arc KM = 61°

Substitute

70° = ½(Arc KN - 61°)

2*70° = Arc KN - 61°

140° = Arc KN - 61°

140° + 61° = Arc KN

201° = Arc KN

Arc KN = 201°

Answer:

12*12=144

8*10=80

80+144=224

224*2=448

10*4=40

8*10=80

80*2=160

40+160=200

12*10=120

120+200=320

20*10=200

320+200=520

448+520=968

Hope This Helps!!!

Answer:

C.

Step-by-step explanation:

Answer:

either it's 1:3 or 1:6

Step-by-step explanation:

3 students went to the zoo, and 15 students went to the aquarium.

15 plus 3 is 18.

3/18 then reduces to 1/6

therefore it is:

1:6

(before, I got my answer deleted so, maybe it is 1:3, but I solved it and got 1:6)

Answer:

The unknown number is [tex]\frac{1}{5}[/tex]

Step-by-step explanation:

Let's make the unknown number x.

The sum of 5 TIMES a number (x) & 8 is 9.

Let's write it mathematically.

5x + 8 =9

We are trying to find the unknown number, so let's remove all the numbers from the left side to find x. Minus 8.

5x=1

5x is basically 5 times x, so to find x, we need to divide and from there we can remove 5.

x= [tex]\frac{1}{5}[/tex]

The Euler's formula relates the vertices, faces and the edges of a polyhedron.

The correct option is (e) [tex]V = 6[/tex]    [tex]E = 10[/tex]    [tex]F = 6[/tex]     [tex]6- 10 + 6 = 2[/tex]

First, we count the number of faces. This is the flat parts of the shape.

The attached shape has 6 flat surfaces.

So:

[tex]F = 6[/tex]

Next, we count the number of edges. This is where two faces meet.

The attached shape has 10 edges;

So:

[tex]E = 10[/tex]

Lastly, we count the number of vertices. This is where two edges meet.

The attached shape has 6 vertices.

So:

[tex]V = 6[/tex]

Using Euler's formula, we have:

[tex]V - E + F = 2[/tex]

Substitute values for V, E and F

[tex]6- 10 + 6 = 2[/tex]

[tex]2 = 2[/tex]

Hence, the polyhedron has 6 vertices, 10 edges and 6 faces

Read more vertices, edges, and faces at:

https://brainly.com/question/23347978

Answer:

[tex]\frac{2}{a-b}[/tex]

Step-by-step explanation:

Given

[tex]\frac{1}{a+b}[/tex] + [tex]\frac{1}{a-b}[/tex] + [tex]\frac{2b}{a^2-b^2}[/tex] ← a² - b² is a difference of squares

= [tex]\frac{1}{a+b}[/tex] + [tex]\frac{1}{a-b}[/tex] = [tex]\frac{2b}{(a-b)(a+b)}[/tex] ← LCD is (a - b)(a+b)

= [tex]\frac{a-b+a+b+2b}{(a-b)(a+b)}[/tex]

= [tex]\frac{2a+2b}{(a-b)(a+b)}[/tex]

= [tex]\frac{2(a+b)}{(a-b)(a+b)}[/tex] ← cancel common factor (a + b) on numerator/ denominator

= [tex]\frac{2}{a-b}[/tex]

Answer:

3/7

Step-by-step explanation:

there are is a total of 7 socks and 3 are blue making blue socks be 3/7

Answer:

y=-4x+1

Step-by-step explanation:

Equation: y=mx+b where m = slope and b= y intercept

TO find the slope, find the change in y over the change in x , or just to rise over run

From (-1,5) to (0,1), the y changes by -4 and the x changes by 1.

So the slope will be -4

To find the y intercept, find the point at which the line crosses the y-axis.

In this case, it is at (0, 1), so your y intercept will be 1

Plug all this info back into the equation and you get y=-4x+1

The y-intercept is 1 and that’s it sorry I can’t answer the rest.

9514 1404 393

Answer:

  $36,259.78

Step-by-step explanation:

The formula for compound interest is ...

  A = P(1 +r/n)^(nt)

where principal P is invested at annual rate r for t years compounded n times per year.

Here, you have P = 17000, r = 0.06, n = 1, t = 13.

  A = 17000(1 +0.06)^13 = 17000(2.13292826) = 36,259.78

The accumulated value after 13 years is $36,259.78.

Answer:

73

Step-by-step explanation:

17×2=34

180-34=146

146/2=73

=73

Answer:

n = 3

m = -1/2

Step-by-step explanation:

Multiply the second equation by 4

4(n - 2)x + y = 4(n + m)          Y is now correct.

4(n - 2) = 4                              Remove the brackets    

4n - 8 = 4                                Add 8 to both sides

4n = 8 + 4                               Combine

4n = 12                                    Divide by 4

n = 3                                        x is now correct

4(n - 2) = 4

4(3 -2) = 4

4 = 4

Now you have to worry about m

4(n + m) = 10

n = 3

4(3 + m) = 10                               Divide by 4

m + 3 = 10/4

m + 3 = 2.5                                 Subtract 3 from both sides.

m = 2.5 - 3

m = - 1/2  

2z+16+124=180

2z=180-16-124

2z=40

z=40/2

Z=20°

I hope I helped you ^_^

Sai vì số Nguyên dương nhỏ trừ số nguyên dương lớn bằng số nguyên âm

Answer:

A

Step-by-step explanation:

The area of figure=Area of rectangle+Area of triangle

Area of figure=(x+2)(x-3)+1/2*(x)*(x+2)

Area of figure=x^2-x-6+0.5*x^2+x

Area of figure=(3/2)x^2-6

Answer:

A, M(x)=3/2 (x^2-6)

Step-by-step explanation:

Let's calculate the area of the figure 1st,

Area of figure=Area of triangle+Area of rectangle

                      =1/2 b*h + l*b = 1/2 (x+2)x + (x+2)(x-3)

                      =(x^2+2x)/2+x^2 - x - 6 =(x^2+2x+2x^2 - 2x -12)/2

                      =3x^2-12/2=3/2(x^2-6)

In the options,

M(x)=3/2 (x^2-6) is given, so it best represents the area.

Answer:

hello,

answer 2

Step-by-step explanation:

[tex]I\ note\ Log\ ,log_{10}\\\\4*Log(2)-Log(48)+Log(300)\\\\=4*Log(2)-Log(3*2^4)+Log(3*100)\\\\=4Log(2)-Log(3)-4Log(2)+Log(3)+2*Log(10)\\\\=2*1\\\\=2\\[/tex]

Answer:

the answer is easy  

number 2 is the answer for this question  

Answer:

[tex]7500 {y}^{9} [/tex]

Step-by-step explanation:

[tex] { - 5}^{4} \times {4y}^{10} \times { - 3y}^{ - 1} [/tex]

[tex] = 12 \times {5}^{4} {y}^{9} [/tex]

[tex] = 12 \times 625 {y}^{9} [/tex]

[tex] = 7500 {y}^{9} [/tex]

Answer and explanation:

How are the two methods similar? They both apply the fundamentals of triangle geometry in solving the area of a triangle using the formula for area of triangle 1/2×base of triangle×height of triangle.

How are they different? Using coordinate algebra in finding area of a triangle, you would have to measure coordinates(xy coordinates) of a triangle manually on the graph and find y coordinates based on x. If you used a geometry software, it would get these coordinates automatically(based on your graph on the software) and calculate area of triangle using the formula.

Why might coordinate algebra be important in making and using geometry software? A solid grasp of coordinate algebra allows you understand how the geometry software works because it makes use of same geometry fundamentals, making it easier for you to tweak and get the best value out of the software for your geometry calculations.

Answer:

They all use the same formula for area of triangle 1/2 base of triangle height of triangle to identify the area of a triangle using the essentials of triangle geometry.To find the area of a triangle using coordinate algebra, you must configure way of measuring the triangle's coordinates like the x and y coordinates on the graph and afterwards find the y coordinates depending on the x coordinates. If you were using geometry software, it would immediately determine the area of the triangle by using formula based on your graph on the software.Because geometry software uses the same geometry basic concepts as coordinate algebra, having a proper understanding of coordinate algebra makes it simpler to improve.

Step-by-step explanation: im sorry if this doesn't help or if its incorrect more than welcomed to add some stuff to it!

Answer:

5

Step-by-step explanation:

The distance is given by sqrt((-3-0)^2+(-3-1)^2)=sqrt(9+16)=5

Answer:

I believe the distance equals 5

Step-by-step explanation:

Use the distance formula and plug in the numbers. Then solve.

Answer:

(1,-4)

Step-by-step explanation:

We add 4 to the x-coordinate, so -3+4=1.

Answer:

45g

Step-by-step explanation:

The amount of salt left once the whole water is evaporated can be calculated as follows

= 12% × 375

= 12/100 × 375

= 0.12×375

= 45

Hence 45g of salt is left after the evaporation of water

Answer:

45g

Step-by-step explanation:

Answer:

Volume = 108 ft³

Step-by-step explanation:

Volume of a sphere is given by the expression,

V = [tex]\frac{4}{3}\pi r^{3}[/tex]

Here, r = Radius of the sphere

From the picture attached,

Radius of the sphere = 3 ft

By substituting the value of r in the expression,

Volume = [tex]\frac{4}{3}\pi (3)^{3}[/tex]

             = 36π

             = 36×3

             = 108 ft³

Answer: x = 24

Step-by-step explanation:

There are two triangles here; all angles in a triangle add up to 180, so in the first triangle we have two angles.

We add 94 and 41 together, and this gives us 135.

Now, we find the third angle of this triangle and the angle of the inner triangle by doing 180 - 135.

This gives us 45, and now we can calculate for x using the same method we used above.

111 + 45 = 156

180 - 156 = 24

Thus, x is equal to 24 degrees.

Hi there!  

»»————-　★　————-««

I believe your answer is:  

4

»»————-　★　————-««  

Here’s why:  

⸻⸻⸻⸻

[tex]\boxed{\text{Calculating the Answer...}}\\\\15+(-11)\\----------------\\\rightarrow 15 +1(-11)\\\\\rightarrow 15 - 11\\\\\rightarrow \boxed{4}[/tex]

⸻⸻⸻⸻

»»————-　★　————-««  

Hope this helps you. I apologize if it’s incorrect.  

your answer will obviously be 4