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2 years ago

X^(2)+x-20 splitting the middle term

1 answer:

5 0

Are you trying to factorise this?

Here is a way you may not have been taught....
(x + a)(x + b) = x^2 + (a + b)x + ab

So you need to find two factors of -20 that add up to +1
-4 x 5 = -20 and -4 + 5 = 1. Perfect

x^2 + x - 20 = (x - 4)(x + 5)

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Suppose you take an SRS of size 1000 of Connecticut students eligible to take the SAT and find that 85% plan to take the SAT dur

nadezda [96]

Answer:

$\mu_{p}=p=0.81$

Step-by-step explanation:

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

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 population proportion have the following distribution

$p \sim N(p,\sqrt{\frac{p(1-p)}{n}})$

So under the null hypothesis the mean for the population proportion is p

$\mu_{p}=p=0.81$

And the standard deviationis given by:

$\sigma_{p}=\sqrt{\frac{p_0(1-p_o)}{n}}=\sqrt{\frac{0.81(1-0.81)}{1000}}=0.0124$

7 0

3 years ago

Find the coordinates of the other endpoint of the segment, given its midpoint and one endpoint. (Hint: Let (x,y) be the unkno

spin [16.1K]

The other endpoint is (1, -17).

The midpoint formula is:

$m=(\frac{x_1+x_2}{2}, \frac{y_1+y_2}{2})$

Using our midpoint and endpoint, we have:
$(6, -11) = (\frac{11+x_2}{2}, \frac{-5+y_2}{2})
\\
\\6=\frac{11+x_2}{2} \text{ and } -11=\frac{-5+y_2}{2}
$

For the first equation (to find the x-coordinate) we will multiply both sides by 2:
$6\times2=\frac{11+x_2}{2}\times 2
\\
\\12=11+x_2$

Subtract 11 from both sides:
12 - 11 = 11+x₂ - 11
1 = x₂

For the second equation (the y-coordinate) we multiply both sides by 2:
$-11\times2=\frac{-5+y_2}{2}\times 2
\\
\\-22=-5+y_2$

Add 5 to both sides:
-22+5 = -5+y₂ + 5
-17 = y₂

This means that (x₂, y₂) is at (1, -17).

4 0

3 years ago

Find the mean, median, mode, and range of this data: 49, 49, 54, 55, 52, 49, 55. If necessary, round to the nearest tenth.

Darya [45]

Mean: 51.9
Median: 52
Mode: 49
Range: 6

3 0

3 years ago

Read 2 more answers

Pls explain how you figured out both questions

Mariana [72]

Answer:

A=0.125

B=0.125

Step-by-step explanation

for both you would divide 0.5 by 4. you would cut 0.125 off of each side, but two sides together would 0.25

6 0

3 years ago

What is 3 to the -2

melomori [17]

Answer:

1/9

Step-by-step explanation:

Anything to the negative power will be under 1

So take the square and then reciprocate it.

3 0

3 years ago