4x - 2y = 20 -8.x

Simplify the expression.

netineya [11]

Answer:

-6m^2 *n^2

Step-by-step explanation:

formula: (m^x)/(m^y)= m^(x-y)

apply formula for (4m^2)/(2m^-3)

=(4m^(2--3)/(2)

=4m^5/2

divide 4/2

=2m^5

next part 3n^5/(-mn)^3

3n^5/(-mn)^3

expand

=3n^5/ (-m^3*n^3)

=3n^(5-3)/ -m^3

=3n^2/ -m^3

both parts:

(2m^5* 3n^2)/ -m^3

= -(2m^5* 3n^2)/ m^3

= -(2m^(5-3)* 3n^2)/ 1

= -(2m^2* 3n^2)

= -(6m^2*n^2)

= -6m^2 *n^2

8 0

1 year ago

In a recent year, the ACT scores for the math portion of the test were normally distributed, with a mean of 21.1 and a standard

Natali5045456 [20]

Answer:

a) $P(X$

And we can find this probability using the normal standard table or excel:

$P(z$

b) $P(19$

And we can find this probability with this difference:

$P(-0.396$

And in order to find these probabilities we can use tables for the normal standard distribution, excel or a calculator.

$P(-0.396$

c) $P(X>26)=P(\frac{X-\mu}{\sigma}>\frac{26-\mu}{\sigma})=P(Z>\frac{26-21.1}{5.3})=P(z>0.925)$

And we can find this probability using the complement rule and the normal standard table or excel:

$P(z>0.925)=1- P(Z$

d) We can consider unusual events values above or below 2 deviations from the mean

$Lower = \mu -2*\sigma = 21.1 -2*5.3 =10.5$

A value below 10.5 can be consider as unusual

$Upper = \mu +2*\sigma = 21.1 +2*5.3 =31.7$

A value abovr 31.7 can be consider as unusual

Step-by-step explanation:

Previous concepts

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".

Part a

Let X the random variable that represent the scores of a population, and for this case we know the distribution for X is given by:

$X \sim N(21.1,5.3)$

Where $\mu=21.1$ and $\sigma=5.3$

We are interested on this probability

$P(X$

And the best way to solve this problem is using the normal standard distribution and the z score given by:

$z=\frac{x-\mu}{\sigma}$

If we apply this formula to our probability we got this:

$P(X$

And we can find this probability using the normal standard table or excel:

$P(z$

Part b

$P(19$

And we can find this probability with this difference:

$P(-0.396$

And in order to find these probabilities we can use tables for the normal standard distribution, excel or a calculator.

$P(-0.396$

Part c

$P(X>26)=P(\frac{X-\mu}{\sigma}>\frac{26-\mu}{\sigma})=P(Z>\frac{26-21.1}{5.3})=P(z>0.925)$

And we can find this probability using the complement rule and the normal standard table or excel:

$P(z>0.925)=1- P(Z$

Part d

We can consider unusual events values above or below 2 deviations from the mean

$Lower = \mu -2*\sigma = 21.1 -2*5.3 =10.5$

A value below 10.5 can be consider as unusual

$Upper = \mu +2*\sigma = 21.1 +2*5.3 =31.7$

A value abovr 31.7 can be consider as unusual

6 0

2 years ago

What is the amplitude of the sinusoid's graph? y = -4 sin 3x

GrogVix [38]

Answer:

Amplitude = 4

Step-by-step explanation:

The general form of a sine curve would be $y=ASin(bx)$ where A is the "amplitude", or the "tallness" or "shortness" of the graph.

Technically, amplitude is the absolute value of the number that is multiplied in front of "Sin". So the amplitude is 4.

Note: The negative sign in front of 4 plays the role of "flipping" the curve upside down.

6 0

2 years ago

Jenny makes quilts. she can make 7 quilts with 21 yards of material. how many yards of material would be required to make 12 qui

kozerog [31]

3 yards per quilt

36 for 12

8 0

3 years ago

Read 2 more answers

Solve the equation x^2 - 4x + 6 = 9 by completing the square.

tatuchka [14]

Hello!

x² - 4x + 6 = 9 <=>

<=> x² - 4x + 6 - 9 = 0 <=>

<=> x² - 4x - 3 = 0 <=>

<=> x = -(-4)±√(-4)²-4×1×(-3)/2×1 <=>

<=> x = 4±√16+12/2 <=>

<=> x = 4±√28/2 <=>

<=> x = 4±2√7/2 =>

=> x = 4+2√7/2 and x = 4-2√7/2 =>

=> x = 2+√7 and x = 2-√7

The equation has two solutions.

Good luck! :)

7 0

2 years ago

Read 2 more answers

4x - 2y = 20 -8.x - 3y = 16