2. Write (2+5i)(3-1) as a complex number in standard form a+bi.<br> real part + imaginary part

Why don't we measure spread about the mean by simply averaging x − x , the deviations of individual data values from their mean?

skad [1K]

Answer:

Because this spread will add up to zero

Step-by-step explanation:

Mean defines the center of the data. Some values are below this center and some values are above this center.

For the values which are below the center (i.e. less than the mean), when mean is subtracted from these values, this results in negative numbers.

For the values which are above the center(i.e. greater than the mean), when mean is subtracted from these values, this results in positive numbers.

When these negative and positive numbers are summed together, as it is, they cancel out each other, leaving an answer equal to zero, which would be meaningless. As a spread of 0 would mean all data values are the same, when infact they aren't.

To avoid this, the difference of mean from the data value is squared, so that we can get all positive values, and then these values are added up together to calculate the spread of the data.

Conclusion:

The average of deviations of individual data from the mean will result in answer equal to zero, as a result they are squared first before finding the average.

7 0

3 years ago

Whoever answers question 19 correctly with both parts of the questions answered

diamong [38]

Let's focus on 0.7*0.8 for now.

Start by drawing a large square. Cut this figure into 10 rows and 10 columns. So this means you'll have 10*10 = 100 little squares.

Now highlight the first 7 rows. Shade in all 70 squares (7*10 = 70)
Starting on the left side, highlight the first 8 columns. You'll shade in 80 squares (8*10 = 80)

Use different colors for your highlighting or somehow indicate different shading styles. This way you can see the overlapping region. The overlapping region consists of 56 squares (7 rows, 8 columns ---> 7*8 = 56 little squares)

Each little square represents 0.01, so having 56 of them means we have 0.56

This shows that 0.7*0.8 = 0.56

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

How is this different if we had 1.7*0.8? Well we can break 1.7 into 1+0.7 to have

1.7*0.8 = (1+0.7)*0.8
1.7*0.8 = (1)*0.8+(0.7)*0.8
1.7*0.8 = (1*0.8)+(0.7*0.8)

The portion (0.7*0.8) was done earlier. That result was 0.56. So we just need to compute (1*0.8), which is simply 0.8; recall that 1 times any number is that number itself.

Now simply add 0.8 to 0.56 to get 1.36

So, 1.7*0.8 = 1.36

5 0

3 years ago

A sphere is cut into 8 congruent pieces. The radius of the

BartSMP [9]

Answer:

64pi cm^2

i think

Step-by-step explanation:

6 0

3 years ago

Read 2 more answers

18-2x+10=12x solve for x

Scorpion4ik [409]

Answer:

x=2

Step-by-step explanation:

18-2x+10=12x

-2x+18+10=12x

-2x+28=12x

subtract 28 from both sides= -2x=12x-28

subtract 12x from both sides= -14x=-28

divide both sides by -14= x=2

x=2 is your final answer

8 0

3 years ago

Read 2 more answers

The slope of a line on a distance-time graph represents

Dovator [93]

Answer:

speed

Step-by-step explanation:

In a distance-time graph:

Distance is the y-variable (dependent)

Time is the x-variable (independent)

The slope of a line is rise/run, or can also be calculated with this equation, where "m" is slope:

$m = \frac{y_{2}-y_{1}}{x_{2}-x_{1}}$

slope = y-variables / x-variables

slope = distance / time

If you divide distance by the time it took to get that far, you will find how fast you got there. This is called the speed.

You might also see this formula:

k = d/t

In the options, "time" and "distance" would not make sense, because those are the variables on the x-axis and y-axis.

8 0

3 years ago

2. Write (2+5i)(3-1) as a complex number in standard form a+bi. real part + imaginary part