PLEASE HELP ME!!!!!<br><br>ABCD is a parallelogram. Find x.

in a certain town there are 30000 registered voters, of whom 12000 are Democrats. A survey organization is about to take a simpl

mario62 [17]

Answer:

400.

Step-by-step explanation:

The following data were obtained from the question:

Total number of Registered voters = 30000

Total number of Democrats = 12000

Next, we shall determine the percentage of Democrats in the registered voters.

This can be obtained as follow:

Percentage of Democrats = number of Democrats / Total number of registered voters x 100

Percentage of Democrats = 12000/30000 x 100

Percentage of Democrats = 40%

Now, we can obtain the expected value of percentage of Democrats in the 1000 sample as follow:

Percentage of Democrats = 40%

Total number of Sample = 1000

Number of Democrats in the sampl=..?

Percentage of Democrats = number of Democrats in sample / Total number of sample x 100

40% = number of Democrats in sample/1000

Cross multiply

Number of Democrats in sample

= 40% x 1000

= 40/100 x 1000

= 400

Therefore, the expected number of Democrats in the sample is 400.

4 0

2 years ago

Rationalize the denominator of sqrt -49 over (7 - 2i) - (4 + 9i)

zubka84 [21]

$\sqrt{ \frac{-49}{(7-2i)-(4+9i) } } 
$

This one is quite the deal, but we can begin by distributing the negative on the denominator and getting rid of the parenthesis:

$\frac{ \sqrt{-49}}{7-2i-4-9i}$

See how the denominator now is more a simplification of like terms, with this I mean that you operate the numbers with an "i" together and the ones that do not have an "i" together as well. Namely, the 7 and the -4, the -2i with the -9i.
Therefore having the result:

$\frac{ \sqrt{-49} }{3-11i}$

Now, the $\sqrt{-49}$ must be respresented as an imaginary number, and using the multiplication of radicals, we can simplify it to $\sqrt{49} \sqrt{-1}$
This means that we get the result 7i for the numerator.

$\frac{7i}{3-11i}$

In order to rationalize this fraction even further, we have to remember an identity from the previous algebra classes, namely: $x^2 - y^2 =(x+y)(x-y)$
The difference of squares allows us to remove the imaginary part of this fraction, leaving us with a real number, hopefully, on the denominator.

$\frac{7i (3+11i)}{(3-11i)(3+11i)}$

See, all I did there was multiply both numerator and denominator with (3+11i) so I could complete the difference of squares.
See how $(3-11i)(3+11i)= 3^2 -(11i)^2$ therefore, we can finally write:

$\frac{7i(3+11i)}{3^2 - (11i)^2 }$

I'll let you take it from here, all you have to do is simplify it further.
The simplification is quite straightforward, the numerator distributed the 7i. Namely the product $7i(3+11i) = 21i+77i^2$ .
You should know from your classes that i^2 = -1, thefore the numerator simplifies to $-77+21i$
You can do it as a curious thing, but simplifying yields the result:
$\frac{-77+21i}{130}$

7 0

3 years ago

Please help me I really need help

omeli [17]

It's basically asking you how far away is each dot. The graph goes by six. Good luck

3 0

3 years ago

Un automovil gasta 6 litros cada 110 kilometros ¿cuantos kilometros recorrera con 22 litros

natulia [17]

Answer:

403.33 kilometros

Step-by-step explanation:

De la pregunta anterior:

6 litros = 110 kilómetros

22 litros = x

Cruz multiplicar

6 litros × x = 22 litros × 110 kilómetros

x = 22 litros × 110 kilómetros / 6 litros

x = 403.33 kilometros

Así, 22 litros recorrerán 403.33 kilómetros

7 0

2 years ago

Consider he following table. Does the table represent a function? Why or why not?

Damm [24]

This is considered a function because each input has a different output. For example, a certain x value doesnt equal 2 different y values, making this a function. Take this: if there is (2,4) and (3,4), this is a function because although the y values are the same, the x values are different. (2,3) and (2,4) do not convey a function because the x values are the same, but each has a different y value.
hope this helped!!!
brainliest answer, please?

6 0

2 years ago

PLEASE HELP ME!!!!!ABCD is a parallelogram. Find x.