(-4,9), (-4 -3), and (-1, 9) what is the area?

A triangle has sides of lengths 9,7, and 12. Is it a right triangle? Explain.

Alex Ar [27]

Answer:

A triangle has sides of lengths 9,7, and 12 is not a right triangle .

7 0

3 years ago

Gina bought 2.5 pounds of peaches that cost $1.38 per pound at the grocery store. Amy went to the local farmer’s market and purc

patriot [66]

Gina spent $3.45 in total. amy spent $3.43 in total. so gina spent more money and she spent 2 cents more

4 0

2 years ago

Read 2 more answers

The amount of lateral expansion (mils) was determined for a sample of n = 8 pulsed-power gas metal arc welds used in LNG ship co

Alona [7]

Answer:

95% Confidence interval for the variance:

$3.6511\leq \sigma^2\leq 34.5972$

95% Confidence interval for the standard deviation:

$1.9108\leq \sigma \leq 5.8819$

Step-by-step explanation:

We have to calculate a 95% confidence interval for the standard deviation σ and the variance σ².

The sample, of size n=8, has a standard deviation of s=2.89 miles.

Then, the variance of the sample is

$s^2=2.89^2=8.3521$

The confidence interval for the variance is:

$\dfrac{ (n - 1) s^2}{ \chi_{\alpha/2}^2} \leq \sigma^2 \leq \dfrac{ (n - 1) s^2}{\chi_{1-\alpha/2}^2}$

The critical values for the Chi-square distribution for a 95% confidence (α=0.05) interval are:

$\chi_{0.025}=1.6899\\\\\chi_{0.975}=16.0128$

Then, the confidence interval can be calculated as:

$\dfrac{ (8 - 1) 8.3521}{ 16.0128} \leq \sigma^2 \leq \dfrac{ (8 - 1) 8.3521}{1.6899}\\\\\\3.6511\leq \sigma^2\leq 34.5972$

If we calculate the square root for each bound we will have the confidence interval for the standard deviation:

$\sqrt{3.6511}\leq \sigma\leq \sqrt{34.5972}\\\\\\1.9108\leq \sigma \leq 5.8819$

6 0

3 years ago

Sally was standing 30 feet from a tree. The angle of

QveST [7]

Answer: The tree was 27 feet tall

Step-by-step Explanation: First of all Sally was standing 30 feet away from the tree and she looks up at an angle of elevation of 38 degrees to the top of the tree. With this bit of information we can determine that a right angled triangle has been formed with the reference angle as 38 degrees, the side facing it as h (the height of the tree) and the adjacent side as 30. We shall apply the trigonometric ratio as follows;

Tan 38 = opposite/adjacent

Tan 38 = h/30

0.7813 = h/30

0.7813 x 30 = h

23.4 = h

We remember at this point that Sally’s eyes were 4 feet above the ground. What we have just calculated is the height of the tree from “4 feet above the ground” (where her eyes were). Hence the actual height of the tree is calculated as 23.4 plus 4 which gives us 27.4

Therefore the tree was 27 feet tall (approximately to the nearest foot)

5 0

3 years ago

Determine the slope of the line that passes through the points (-4, 6) and (0, 4).

slamgirl [31]

The slope of the line that passes through those points is: B) -1/2

5 0

3 years ago