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3 years ago

What is the length of BC¯¯¯¯¯ ?

Mathematics

2 answers:

adell [148]3 years ago

3 0

X + 9 = 2x - 8
2x - x = 9 + 8
x = 17

BC = x = 17

answer
17 units

alexgriva [62]3 years ago

3 0

You would set AC and AB equal to each other to find out what x is.

x+9=2x-8
x+17=2x
17=1x
17=x

Since CB is just x, CB equals 17.

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Find the area of a regular pentagon with side = 12

zhenek [66]

A=1
45(5+25)a2=1
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247.75

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3 years ago

Read 2 more answers

A field researcher is gathering data on the trunk diameters of mature pine and spruce trees in a certain area. The following are

lidiya [134]

Answer:

As the pvalue of the test is 0.02097 < 0.1, using a .10 significance level, he can conclude that the average trunk diameter of a pine tree is greater than the average diameter of a spruce tree.

Step-by-step explanation:

Using a .10 significance level, can he conclude that the average trunk diameter of a pine tree is greater than the average diameter of a spruce tree

The null hypothesis is that they are equal(that is, subtraction between the means is 0), while the alternate hypothesis is that they are greater(that is, subtraction between the means is larger than 0). So

$H_0: \mu_1 - \mu_2 = 0$

$H_a: \mu_1 - \mu_2 > 0$

In which $\mu_1$ is the mean pine trees height while $\mu_2$ is the mean spruce trees height.

The test statistic is:

$z = \frac{X - \mu}{s}$

In which X is the sample mean, $\mu$ is the value tested at the null hypothesis and s is the standard error.

0 is tested at the null hypothesis:

This means that $\mu = 0$

Mean trunk diameter (cm) 35 30:

Pine trees - 35

Spruce trees - 30

The sample mean is given by the subtraction of the means. So

$X = 35 - 30 = 5$

Sample Size 40 80

Population variance 160 160

This means that the standard error for each sample is given by:

$s_1 = \frac{\sqrt{160}}{\sqrt{40}} = 2$

$s_1 = \frac{\sqrt{160}}{\sqrt{80}} = \sqrt{2}$

The standard error of the difference is the square root of the sum squared of the standard error of each sample.

$s = \sqrt{2^2 + (\sqrt{2})^2} = \sqrt{6} = 2.4495$

Test statistic:

$z = \frac{X - \mu}{s}$

$z = \frac{5 - 0}{2.4495}$

$z = 2.04$

Pvalue of the test:

Probability of a sample mean larger than 5, which is 1 subtracted by the pvalue of Z when X = 5.

Looking at the z-table, z = 2.04 has a pvalue of 0.9793.

1 - 0.9793 = 0.0207

As the pvalue of the test is 0.02097 < 0.1, using a .10 significance level, he can conclude that the average trunk diameter of a pine tree is greater than the average diameter of a spruce tree.

8 0

3 years ago

The graph of f(x)=3•2^x -3 is shown below. G(x) is a transformation of f(x). How would you write the equation for the function g

Bezzdna [24]

Answer:

Step-by-step explanation:

To find the appropriate equation, notice the red graph has shifted up about 6 units. This means that $3*2^x-3$ which is shifted by -3 will move 6 up. -3+6= 3. This means the function will have +3. Only B and C are options. Now test a point. Notice the red function crosses the y-axis at about 5 or 6 when x=0.

$g(x) = 2^x+3\\g(0) = 2^0+3\\g(0)=1+3\\g(0)=4$

This function doesn't match.

$f(0) = 3*2^0+3\\f(0) = 3*1+3\\f(0)=6$

This function matches. Option C is correct.

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3 years ago

To solve y and x, I am adding a picture

Viktor [21]

Answer:

$x =\sqrt 5$

$y = \sqrt{5$

Step-by-step explanation:

Given

The attached triangle

Required

Solve for x

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Solve for y

$y = \sqrt{10} * \cos(45)$

In radical form, we have:

$y = \sqrt{10} * \frac{1}{\sqrt 2}$

$y = \sqrt{10/2}$

$y = \sqrt{5$

To solve for x, we make use of Pythagoras theorem

$x^2 + y^2 = (\sqrt{10})^2$

$x^2 + y^2 =10$

Substitute for y

$x^2 + (\sqrt 5)^2 =10$

$x^2 + 5 =10$

Collect like terms

$x^2 =10-5$

$x^2= 5$

Solve for x

$x =\sqrt 5$

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Lady_Fox [76]

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3 years ago