It cost Joseph $21.90 to send 146 text messages. How many text messages did he send if he spent $6.45?

a) The value of [tex]k'(0)[/tex] is [tex]\frac{3\sqrt{3}}{2}[/tex].

b) The value of [tex]m'(5)[/tex] is approximately -0.034.

c) The value of [tex]x[/tex] is approximately 0.622.

a) [tex]f(x)[/tex] is a piecewise function formed by two linear functions, whose form is defined by the following definition:

[tex]f(x) = \frac{y_{2}-y_{1}}{x_{2}-x_{1}} \cdot x + b[/tex] (1)

Where:

Now we proceed to determine the linear functions:

Line 1: [tex]x \in [-1, 2)[/tex]

[tex](x_{1}, y_{1}) = (0, 3)[/tex], [tex](x_{2}, y_{2}) = (1, 5)[/tex], [tex]b = 3[/tex]

[tex]f(x) = \frac{5-3}{1-0}\cdot x + 3[/tex]

[tex]f(x) = 2\cdot x + 3[/tex]

Line 2: [tex]x \in [2, 8][/tex]

[tex](x_{1}, y_{1}) = (2, 7)[/tex], [tex](x_{2}, y_{2}) = (8, 3)[/tex]

First, we determine the slope of function:

[tex]m = \frac{3-7}{8-2}[/tex]

[tex]m = -\frac{2}{3}[/tex]

Now we proceed to determine the intercept of the linear function:

[tex]7 = -\frac{2}{3}\cdot 2 + b[/tex]

[tex]b = \frac{25}{3}[/tex]

[tex]f(x) = -\frac{2}{3}\cdot x +\frac{25}{3}[/tex]

The first derivative of a linear function is its slope, and the first derivative of a product of functions is defined by:

[tex]k'(x) = f'(x)\cdot g(x) + f(x)\cdot g'(x)[/tex]

If we know that [tex]f(x) = 2\cdot x + 3[/tex], [tex]f'(x) = 2[/tex], [tex]g(x) = \sqrt{x^{2}-x+3}[/tex], [tex]g'(x) = \frac{2\cdot x - 1}{2\cdot \sqrt{x^{2}-x+3}}[/tex] and [tex]x = 0[/tex], then:

[tex]k'(x) = 2\cdot \sqrt{x^{2}-x+3}+\frac{(2\cdot x +3)\cdot (2\cdot x - 1)}{2\cdot \sqrt{x^{2}-x+3}}[/tex]

[tex]k'(0) = 2\sqrt{3}-\frac{3}{2\sqrt{3}}[/tex]

[tex]k'(0) = \frac{12-3}{2\sqrt{3}}[/tex]

[tex]k'(0) = \frac{9}{2\sqrt{3}}[/tex]

[tex]k'(0) = \frac{3\sqrt{3}}{2}[/tex]

The value of [tex]k'(0)[/tex] is [tex]\frac{3\sqrt{3}}{2}[/tex].

b) The derivative is found by means of the formulas for the derivative of the product of a function and a constant and the derivative of a division between two functions:

[tex]m'(x) = \frac{f'(x)\cdot g(x)-f(x)\cdot g'(x)}{2\cdot [g(x)]^{2}}[/tex] (2)

If we know that [tex]f(x) = -\frac{2}{3}\cdot x +\frac{25}{3}[/tex], [tex]f'(x) = -\frac{2}{3}[/tex], [tex]g(x) = \sqrt{x^{2}-x+3}[/tex], [tex]g'(x) = \frac{2\cdot x - 1}{2\cdot \sqrt{x^{2}-x+3}}[/tex] and [tex]x = 5[/tex], then:

[tex]f(5) = 5[/tex]

[tex]f'(5) = -\frac{2}{3}[/tex]

[tex]g(5) = \sqrt{23}[/tex]

[tex]g'(5) = \frac{9\sqrt{23}}{46}[/tex]

[tex]m'(5) = \frac{\left(-\frac{2}{3} \right)\cdot \sqrt{23}-\left(-\frac{2}{3} \right)\left(\frac{9\sqrt{23}}{46} \right)}{3\cdot 25}[/tex]

[tex]m'(5) \approx -0.034[/tex]

The value of [tex]m'(5)[/tex] is approximately -0.034.

c) In this case we must find a value of [tex]x[/tex], so that [tex]h'(x) = 2[/tex]. Hence, we have the following formula below:

[tex]5\cdot e^{x}-9\cdot \cos x = 2[/tex]

A quick approach is using a graphing tool a locate a point so that [tex]5\cdot e^{x}-9\cdot \cos x = 2[/tex]. According to this, the value of [tex]x[/tex] is approximately 0.622.

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Answer:

i think x = -5, y = -7 is a other solution set

Answer:

3/2

Step-by-step explanation:

Since the shape is an equilateral triangle, all the angles are equal measure, 60° and all the sides are also of equal measure that was given, root3. So half of the triangle has length (root3)/2. The perpendicular drawn in the interior is also an angle bisector. The triangles created are 30°-60°-90° triangles. The sides of this special right triangle are in the ratio

s : 2s : sroot3

The longest side of the 30-60-90 triangle is given. The shortest side is half the length of the longest side. The length of the long leg is the short leg × root3

In this diagram the short leg is (root3)/2 .

(root3)/2 × root3 = 3/2

See image.

Here is ur answer of your question

Answer:

84

Step-by-step explanation:

TPS + SPR = RPT and TPS = RPT - SPR

The measure of RPT and SPR are given so we just need to place them and do the calculation

TPS = 137 - 53

TPS = 84

Answer:

The answer is B

Step-by-step explanation:

plug 2 into x to see

A.

x^2 + 8

2^2 + 8

4 + 8 = 12

B.

3x^2 + 1

3(2)^2 + 1

3(4) + 1

12 + 1 = 13

C.

2x^3 + 5

2(2)^3 + 5

2(8) + 5

16 + 5 = 21

D.

x^2 + x

2^2 + 2

4 + 2 = 6

Using proportions, it is found that:

In this question, 42 out of 75 customers voted for the cheddar flavor, hence:

[tex]p = \frac{42}{75}[/tex]

That is, the fraction that shows the proportion of customers who voted for cheddar flavor is [tex]\frac{42}{75}[/tex]

The percentage is:

[tex]\frac{42}{75} \times 100\% = 56\%[/tex]

56% of customers voted for cheddar flavor.

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The general statement that is true about retirement is B. your income will decrease, while your expenses will increase.

Retirement is the leaving of one's of occupation. This means you cease to be involved in active service in a job or occupation especially when one is considered old and of retirement age.

During retirement, retirement benefits and pension are usually made available to retirees. However, one's income will come to a decline which makes most people scared of retirement. Keeping up with the standard of living they are used to becomes difficult as income to sustain such may not be available.

Therefore, the general statement that is true about retirement is B. your income will decrease, while your expenses will increase.

Learn more about retirement on:

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Answer:

It's B

Step-by-step explanation:

Just took it

Answer:

Base = 10 ft. and the height = 6.

Step-by-step explanation:

Area of triangle = 1/2bh

base is 4 + h  ⇔  base = 4 + h

height = h

Using the formula for the area of triangle substitute into the formula the given facts.

A = 1/2bh

30 = 1/2(4 + h) (h)

30 = 1/2(4h + h²)     Multiply both sides by 2

60 = 4h + h²

-60 =           -60      Add -60 to both sides

0 = h²+ 4h -60        

(h + 10)(h - 6) = 0      Factor

h + 10 = 0    h - 6 =0

h = -10         h = 6

reject any negative number and use the positive answer for h.

So h = 6      and the base = 4 + 6 ; base = 10

Answer:

See explanation

Step-by-step explanation:

Dilation of 4

G (0, 1) G' (0, 4)

F (1, 1) F' (4, 4)

Gx'/Gx = 0 / 0 = 0

Gy' / Gy = 4 / 1 = 4

Fx' / Fx = 4 / 1 = 4

Fy' / Fy = 4 / 1 = 4

Answer:

128

Step-by-step explanation:

The cost for filling the pool if the city charges $1.50 per 1000 gallons is $333.97

Given:

Length = 25 yd

width = 26 yd

Height = 5.1 ft

convert yard to feet

25 yd = 75 ft

26 ft = 78 ft

Volume of the pool = length × width× height

= 75 × 78 × 5.1

= 29,835 cubic ft

1 gallon = 0.134 cubic ft.

222,649.3 gallon = 29,835 ft

charges per 1000 gallon = $1.50

Total charges = 222,649.3 gallon / 1000 gallon × $1.50

= 222.6493 × 1.50

= 333.97395

Approximately,

$333.97

Therefore, the cost for filling the pool if the city charges $1.50 per 1000 gallons is $333.97

Learn more about volume:

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Answer:

the first one's right i think

Answer:

40x-17

Step-by-step explanation:

(-3x³+2x²+4x+24) (x-2)

---------------------------------

8x

Answer:

225

Step-by-step explanation:

po ang answer ko

please comment if I'm wrong

Answer:

6311000

Step-by-step explanation:

The first thing we do is calculate the total amount of people in both states. 6.89 x10 raised to the 6th power is equal to 6890000. Then we multiply 5.79 by 10 to the fifth power, which equals to 579000. Then we subtract the numbers, and get 6311000. They want you to answer in standard notation, which is the regular way of writing numbers such as 10, instead of 10^1.

The difference in population

[tex] = (6.89 \times {10}^{6} ) - (5.79 \times {10}^{5} ) \\ = (6.89 \times 10 \times {10}^{5} ) - (5.79 \times {10}^{5} ) \\ = (68.9 \times {10}^{5} ) - (5.79 \times {10}^{5} ) \\ = (68.9 - 5.79) \times {10}^{5} \\ = 63.11 \times {10}^{5} [/tex]

Answer:

[tex]63.11 \times {10}^{5} [/tex]

Hope you could get an idea from here.

Doubt clarification - use comment section.

Answer:

22.5 degrees

Step-by-step explanation:

Complementary angles add up to be 90 degrees. You can model the simple equation [tex]x+3x=90[/tex] where is x is the small angle and 3x is the large angle.

[tex]4x=90\\x=22.5[/tex]

the smaller angle is 22.5 degrees

Answer:

20 I believe because 15 divided by 4 is 3.75 so I then divided 75 by 3.75 giving me 20:)

Step-by-step explanation:

the option you chose (<C~=<Y) is absolutely correct.

Answer:

The first step.

Step-by-step explanation:

Answer:

 (c)  p = vm

Step-by-step explanation:

Momentum, represented by 'p', is the product of mass and velocity. It is a vector quantity, just as velocity is a vector quantity.

  p = vm

Therefore, the solved inequality is z > -4.

Hoped this helped.

[tex]BrainiacUser1357[/tex]

Answer:

C. $32.09, since it's not the fixed cost, it changes based on how much drinks are purchased.

Answer:

cosA=root8/3 is the answer

(a) It looks like you're saying

[tex]\displaystyle F(x) = \int_0^x (t - 3t^2 + 7) \, dt[/tex]

Find the critical points of F(x). By the fundamental theorem of calculus,

F'(x) = x - 3x² + 7

The critical points are where the derivative vanishes. Using the quadratic formula,

x - 3x² + 7 = 0   ⇒   x = (1 ± √85)/6

Compute the second derivative of F :

F''(x) = 1 - 6x

Check the sign of the second derivative at each critical point.

• x = (1 + √85)/6 ≈ 1.703   ⇒   F''(x) < 0

• x = (1 - √85)/6 ≈ -1.370   ⇒   F''(x) > 0

This tells us F attains a minimum of

[tex]F\left(\dfrac{1-\sqrt{85}}6\right) \approx \boxed{-6.080}[/tex]

(b) Split up the domain of F at the critical points, and check the sign of F'(x) over each subinterval.

• over (-∞, -1.370), consider x = -2; then F'(x) = -7 < 0

• over (-1.370, 1.703), consider x = 0; then F'(x) = 7 > 0

• over (1.703, ∞), consider x = 2; then F'(x) = -3 < 0

This tells us that

• F(x) is increasing over ((1 - √85)/6, (1 + √85)/6)

• F(x) is decreasing over (-∞, (1 - √85)/6) and ((1 + √85)/6, ∞)

(c) Solve F''(x) = 0 to find the possible inflection points of F(x) :

F''(x) = 1 - 6x = 0   ⇒   6x = 1   ⇒   x = 1/6

Split up the domain at the inflection point and check the sign of F''(x) over each subinterval.

• over (-∞, 1/6), consider x = 0; then F''(x) = 1 > 0

• over (1/6, ∞), consider x = 2; then F''(x) = -11 < 0

This tells us that

• F(x) is concave up over (-∞, 1/6)

• F(x) is concave down over (1/6, ∞)