Is my answer choice correct ?

NEED IT ASAP What is the value of x in the diagram below? A.18/ ROOT 3 B.18 ROOT 2/ROOT 3 C.18 ROOT 3/ ROOT 2 D. 18 ROOT 2

Ostrovityanka [42]

Answer:

x = B. 18 ROOT 2/ROOT 3

Step-by-step explanation:

There are two Triangles in the diagram above.

Step 1

We would solve for Triangle A First

Using Trigonometric function Cosine

cos θ = adjacent /hypotenuse

θ = 30°

Adjacent = 9 units

Hypotenuse = unknown

cos 30= 9/ Hypothenuse

Cross Multiply

cos 30 × Hypotenuse = 9

Hypotenuse = 9 / cos 30

cos 30 in surd form = √3/2

Hypotenuse = 9/√3/2

Hypotenuse = 9 × 2/√3

= 18/√3 units

Step 2

We would solve for the upper triangle = Triangle B

We are looking for x

θ = 45°

For Triangle B, the Hypotenuse we solved for in Triangle A is equivalent to the adjacent in Triangle B

Therefore ,

Hypotenuse for Triangle A = Adjacent side for Triangle B

θ = 45°

Adjacent = 18/√3 units

Hypotenuse = x = unknown

We would solve for this using Trigonometric function cosine

cos 45 = 18/√3 units / Hypothenuse

Cross Multiply

cos 45 × Hypotenuse = 18/√3 units

Hypotenuse = 18/√3 units / cos 45

cos 45 in surd form = 1/√2

Subtituting, we have

Hypotenuse (x) = 18/√3 units / 1/√2

Hypotenuse (x) = 18/√3 units ×√2/1

= 18× √2/ √3 units

= 18 √2/√3 units

Therefore x = Option B. 18 ROOT 2/ROOT 3

3 0

2 years ago

Use P E M D A S to solve this number problem.

eimsori [14]

Yes your answer is correct

5 0

2 years ago

Read 2 more answers

Let the abbreviation PSLT stand for the percent of the gross family income that goes into paying state and local taxes. Suppose

gavmur [86]

Answer:

Number of families that should be surveyed if one wants to be 90% sure of being able to estimate the true mean PSLT within 0.5 is at least 43.

Step-by-step explanation:

We are given that one wants to estimate the mean PSLT for the population of all families in New York City with gross incomes in the range $35.000 to $40.000.

If sigma equals 2.0, we have to find that how many families should be surveyed if one wants to be 90% sure of being able to estimate the true mean PSLT within 0.5.

Here, we will use the concept of Margin of error as the statement "true mean PSLT within 0.5" represents the margin of error we want.

SO, Margin of error formula is given by;

Margin of error = $Z_(_\frac{\alpha}{2}_ ) \times \frac{\sigma}{\sqrt{n} }$

where, $\alpha$ = significance level = 10%

$\sigma$ = standard deviation = 2.0

n = number of families

Now, in the z table the critical value of x at 5% ( $\frac{0.10}{2} = 0.05$ ) level of significance is 1.645.

SO, Margin of error = $Z_(_\frac{\alpha}{2}_ ) \times \frac{\sigma}{\sqrt{n} }$

0.5 = $1.645 \times \frac{2}{\sqrt{n} }$

$\sqrt{n} =\frac{2\times 1.645 }{0.5}$

$\sqrt{n} =6.58$

n = $6.58^{2}$

= 43.3 ≈ 43

Therefore, number of families that should be surveyed if one wants to be 90% sure of being able to estimate the true mean PSLT within 0.5 is at least 43.

4 0

3 years ago

Choose the option that correctly completes the statement.

Tresset [83]

The answer is:

The measure of an exterior angle of a triangle is equal to the sum of the measures of the remote interior angles.

8 0

3 years ago

Mary's team scores 18 points in the first half and 7 points in the second half. Mary scored a total of 5 points. What fraction o

jek_recluse [69]

Answer:

.2 or 1/5

Step-by-step explanation:

First, calculate the total points by adding the two half's totals together.

7 + 18 = 25

Now, divide the number of points Mary scored by the total.

5 / 25 = 1/5

7 0

3 years ago