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2 years ago

PLEASE SOLVE FOR X WITH A SHORT STEP BY STEP

Mathematics

2 answers:

valkas [14]2 years ago

7 0

Answer: 90 - 15-57 = 18 18 is your answer hope this helped

Step-by-step explanation: plz make brainly

Ket [755]2 years ago

6 0

Answer:

8.17

Step-by-step explanation:

Cos(57)=x/15

15xcos(57)=x

8.17=x

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Ryan has a $3000 bond with a 6% coupon. How much interest wil Ryan receive for this bond every 6 months

katen-ka-za [31]

I know 6% of $3000 is $180

But I don't understand the rest of the question.

8 0

3 years ago

Read 2 more answers

PLZ HELP ASAP SOLID GEOMETRY WORD PROBLEMS

yan [13]

The volume of the candle initially is:
V=Ab*h
Area of the base of the cylinder: Ab=pi*r^2
pi=3.14
Radius of the base: r=4 cm
Height of the cylinder: h=6 cm

Ab=pi*r^2
Ab=3.14*(4 cm)^2
Ab=3.14*(16 cm^2)
Ab=50.24 cm^2

V=Ab*h
V=(50.24 cm^2)*(6 cm)
V=301.44 cm^3

The candle melts at a constant rate of:
r=(60 cm^3)/(2 hours)=(120 cm^3)/(4 hours)=(180 cm^3)/(6 hours)
r=30 cm^3/hour

The amount of candle melted off after 7 hours is:
A=(30 cm^3/hour)*(7 hours)
A=210 cm^3

The percent of candle that is melted off after 7 hours is:
P=(A/V)*100%
P=[(210 cm^3)/(301.44 cm^3)]*100%
P=(0.696656051)*100%
P=69.66560510%
Rounded to the nearest percent
P=70%

Answer: 70%

8 0

3 years ago

For the function f(x) = 7/2x-16, what is the difference quotient for all nonzero values of h?

sergey [27]

Answer:

$\frac{f(x + h) - f(x)}{ h} = \frac{7}{2}$

Step-by-step explanation:

Given

$f(x) = \frac{7}{2}x - 16$

Required

The difference quotient for h

The difference quotient is calculated as:

$\frac{f(x + h) - f(x)}{ h}$

Calculate f(x + h)

$f(x) = \frac{7}{2}x - 16$

$f(x+h) = \frac{7}{2}(x+h) - 16$

$f(x+h) = \frac{7}{2}x+ \frac{7}{2}h- 16$

The numerator of $\frac{f(x + h) - f(x)}{ h}$ is:

$f(x + h) - f(x) = \frac{7}{2}x+ \frac{7}{2}h- 16 -(\frac{7}{2}x - 16)$

$f(x + h) - f(x) = \frac{7}{2}x+ \frac{7}{2}h- 16 -\frac{7}{2}x + 16$

Collect like terms

$f(x + h) - f(x) = \frac{7}{2}x -\frac{7}{2}x + \frac{7}{2}h- 16 + 16$

$f(x + h) - f(x) = \frac{7}{2}h$

So, we have:

$\frac{f(x + h) - f(x)}{ h} = \frac{7}{2}h \div h$

Rewrite as:

$\frac{f(x + h) - f(x)}{ h} = \frac{7}{2}h * \frac{1}{h}$

$\frac{f(x + h) - f(x)}{ h} = \frac{7}{2}$

5 0

2 years ago

Square of a standard normal: Warmup 1.0 point possible (graded, results hidden) What is the mean ????[????2] and variance ??????

LenaWriter [7]

Answer:

$E[X^2]= \frac{2!}{2^1 1!}= 1$

$Var(X^2)= 3-(1)^2 =2$

Step-by-step explanation:

For this case we can use the moment generating function for the normal model given by:

$\phi(t) = E[e^{tX}]$

And this function is very useful when the distribution analyzed have exponentials and we can write the generating moment function can be write like this:

$\phi(t) = C \int_{R} e^{tx} e^{-\frac{x^2}{2}} dx = C \int_R e^{-\frac{x^2}{2} +tx} dx = e^{\frac{t^2}{2}} C \int_R e^{-\frac{(x-t)^2}{2}}dx$

And we have that the moment generating function can be write like this:

$\phi(t) = e^{\frac{t^2}{2}$

And we can write this as an infinite series like this:

$\phi(t)= 1 +(\frac{t^2}{2})+\frac{1}{2} (\frac{t^2}{2})^2 +....+\frac{1}{k!}(\frac{t^2}{2})^k+ ...$

And since this series converges absolutely for all the possible values of tX as converges the series e^2, we can use this to write this expression:

$E[e^{tX}]= E[1+ tX +\frac{1}{2} (tX)^2 +....+\frac{1}{n!}(tX)^n +....]$

$E[e^{tX}]= 1+ E[X]t +\frac{1}{2}E[X^2]t^2 +....+\frac{1}{n1}E[X^n] t^n+...$

and we can use the property that the convergent power series can be equal only if they are equal term by term and then we have:

$\frac{1}{(2k)!} E[X^{2k}] t^{2k}=\frac{1}{k!} (\frac{t^2}{2})^k =\frac{1}{2^k k!} t^{2k}$

And then we have this:

$E[X^{2k}]=\frac{(2k)!}{2^k k!}, k=0,1,2,...$

And then we can find the $E[X^2]$

$E[X^2]= \frac{2!}{2^1 1!}= 1$

And we can find the variance like this :

$Var(X^2) = E[X^4]-[E(X^2)]^2$

And first we find:

$E[X^4]= \frac{4!}{2^2 2!}= 3$

And then the variance is given by:

$Var(X^2)= 3-(1)^2 =2$

7 0

3 years ago

the square of a certain whole number n is n^2. if 60 is a factor of n^2, it's possible that ? is not a factor of n^2. a)16 b)25

DanielleElmas [232]

If 60 is a factor of n², then √60 is a factor of n. However, n is a whole number, so its factors are whole numbers.

Simplify √60:
$\sqrt{60}=\sqrt{4 \times 15}=2\sqrt{15}$

If 2√15 is a factor of a whole number n, then √15 must be another factor to make it a whole number.

$2\sqrt{15} \times \sqrt{15}=2 \times 15=2 \times 3 \times 5$

If 60 is a factor of n², then 2, 3, and 5 must be factors of n. The factors of n² are the squares of the factors of n, so 2, 2, 3, 3, 5, and 5 must be factors of n².

Now, if 2, 2, 3, 3, 5, and 5 are factors of n², then:
* 5×5=25 must also be its factor
* 2×2×3×3=36 must also be its factor
* 2×2×5×5=100 must also be its factor

Only 16 may not be a factor of n². The answer is A.

4 0

3 years ago