Triangle ABC is shown BCD=30 D is a point on side AC such that BD=DA=AB prove that AD =DC

Triangle ABC Is Shown BCD=30 D Is A Point On Side AC Such That BD=DA=AB Prove That AD =DC

Answers

Answer 1

Answer:

Step-by-step explanation:

what grade are you on lemme help you

Answer 2

Answer:

<BAC=<BAD=60° (ΔABD is an equilateral triangle (all sides are equal) so each angle measures 60°)

All the angles in a triangle add to 180, so for ΔABC, we can write <ABC=180-60-30=90. So ΔABC is a right angled triangle with hypotenuse AC.

sinA=opposite/hypotenuse

sin30=AB/AC

1/2=AB/AC

AC=2AB=2AD

AC=AD+DC

AD+DC=2AD

DC=AD

QED


Related Questions

Use the remainder theorem to determine which of the following is not a factor of x^3-5x^2-x+5

Answers

Answer:

The answer is A

Step-by-step explanation:

x to the power of 1 is the lowest x and when you multiply -5 and -5 you get 5 so the answer is A.

NASA is conducting an experiment to find out the fraction of people who black out at G forces greater than 6. In an earlier study, the population proportion was estimated to be 0.3 . How large a sample would be required in order to estimate the fraction of people who black out at 6 or more Gs at the 80% confidence level with an error of at most 0.03

Answers

Answer:

A sample of 383 would be required.

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]1-\alpha[/tex], we have the following confidence interval of proportions.

[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]

In which

z is the zscore that has a pvalue of [tex]1 - \frac{\alpha}{2}[/tex].

The margin of error is:

[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]

In an earlier study, the population proportion was estimated to be 0.3.

This means that [tex]\pi = 0.3[/tex]

80% confidence level

So [tex]\alpha = 0.2[/tex], z is the value of Z that has a pvalue of [tex]1 - \frac{0.2}{2} = 0.9[/tex], so [tex]Z = 1.28[/tex].

How large a sample would be required in order to estimate the fraction of people who black out at 6 or more Gs at the 80% confidence level with an error of at most 0.03?

A sample of n is needed.

n is found when M = 0.03. So

[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]

[tex]0.03 = 1.28\sqrt{\frac{0.3*0.7}{n}}[/tex]

[tex]0.03\sqrt{n} = 1.28\sqrt{0.3*0.7}[/tex]

[tex]\sqrt{n} = \frac{1.28\sqrt{0.3*0.7}}{0.03}[/tex]

[tex](\sqrt{n})^2 = (\frac{1.28\sqrt{0.3*0.7}}{0.03})^2[/tex]

[tex]n = 382.3[/tex]

Rounding up:

A sample of 383 would be required.

There are 2.54 centimeters in 1 inch. There are 100 centimeters in 1 meter.
To the nearest inch, how many inches are in 8 meters?

Answers

Answer:

314.96in

Step-by-step explanation:

A 1/17th scale model of a new hybrid car is tested in a wind tunnel at the same Reynolds number as that of the full-scale prototype. The drag coefficient of the model is the same as that of the prototype. Assuming the model and prototype are both tested in air, find the ratio of the drag on the scale model (Fm) to the drag on the prototype (Fp), i.e., Fm/Fp. Since the size of the model is 1/17th of the size of the prototype, the projected area of the model is (1/17)2 of the projected area of the prototype. Round your answer to the nearest tenth.

Answers

Answer:

The ratio of the drag coefficients [tex]\dfrac{F_m}{F_p}[/tex] is approximately 0.0002

Step-by-step explanation:

The given Reynolds number of the model = The Reynolds number of the prototype

The drag coefficient of the model, [tex]c_{m}[/tex] = The drag coefficient of the prototype, [tex]c_{p}[/tex]

The medium of the test for the model, [tex]\rho_m[/tex] = The medium of the test for the prototype, [tex]\rho_p[/tex]

The drag force is given as follows;

[tex]F_D = C_D \times A \times \dfrac{\rho \cdot V^2}{2}[/tex]

We have;

[tex]L_p = \dfrac{\rho _p}{\rho _m} \times \left(\dfrac{V_p}{V_m} \right)^2 \times \left(\dfrac{c_p}{c_m} \right)^2 \times L_m[/tex]

Therefore;

[tex]\dfrac{L_p}{L_m} = \dfrac{\rho _p}{\rho _m} \times \left(\dfrac{V_p}{V_m} \right)^2 \times \left(\dfrac{c_p}{c_m} \right)^2[/tex]

[tex]\dfrac{L_p}{L_m} =\dfrac{17}{1}[/tex]

[tex]\therefore \dfrac{L_p}{L_m} = \dfrac{17}{1} =\dfrac{\rho _p}{\rho _p} \times \left(\dfrac{V_p}{V_m} \right)^2 \times \left(\dfrac{c_p}{c_p} \right)^2 = \left(\dfrac{V_p}{V_m} \right)^2[/tex]

[tex]\dfrac{17}{1} = \left(\dfrac{V_p}{V_m} \right)^2[/tex]

[tex]\dfrac{F_p}{F_m} = \dfrac{c_p \times A_p \times \dfrac{\rho_p \cdot V_p^2}{2}}{c_m \times A_m \times \dfrac{\rho_m \cdot V_m^2}{2}} = \dfrac{A_p}{A_m} \times \dfrac{V_p^2}{V_m^2}[/tex]

[tex]\dfrac{A_m}{A_p} = \left( \dfrac{1}{17} \right)^2[/tex]

[tex]\dfrac{F_p}{F_m} = \dfrac{A_p}{A_m} \times \dfrac{V_p^2}{V_m^2}= \left (\dfrac{17}{1} \right)^2 \times \left( \left\dfrac{17}{1} \right) = 17^3[/tex]

[tex]\dfrac{F_m}{F_p} = \left( \left\dfrac{1}{17} \right)^3[/tex]= (1/17)^3 ≈ 0.0002

The ratio of the drag coefficients [tex]\dfrac{F_m}{F_p}[/tex] ≈ 0.0002.

40 POINTS!!!

Two construction companies are building homes in a new neighborhood. Company A has built 18 homes and plans to build an additional 6 homes each month. Company B has built 41 homes and plans to build an additional 4 homes each month. if building goes according to their plans, in how many months will the total number of homes built by the companies be equal to each other?

Answers

Answer:

14 months until there equal

Answer:

14 months

Step-by-step explanation:

Evaluate the piecewise function when x = -1.

Answers

Step-by-step explanation:

-2<-1<1, so f(-1)=-1-2=-3

The net of a triangular prism is shown
below.
8.5 cm
10 cm
10 cm
10 cm
What is the total surface area of the prism?
A 470 cm?
C 390.5 cm?
B 385 cm
D 342.5 cm

Answers

Answer:

i think a.... sorry if im wrong

Step-by-step explanation:

What is the equation of the following line?

Answers

The the the the the the the answer is of course 3

Answer:

Answer is F. y = 6x

Step-by-step explanation:


What is the area of the parallelogram?

Answers

Answer:

im not 100 percent sure but i think its

140 inches squared

Step-by-step explanation:

Please explain step by step I dont get it.

Answers

Answer: B

Step-by-step explanation:

108 divide by 54 = 2

That equation means she paid 2 dollars per ticket, not 1 dollar for 2 tickets

(There is no 1 in the equation also)

Help pleaseeeeeeeeeeee

Answers

Answer:

3

Step-by-step explanation:

When looking at a graph, the greatest speed will be the steepest part. Even though one line is further than another, does not mean it is faster.

The dot plot below shows the number of movies rented last month by students in Ms. Underwood's class.



What is the median number of movies rented?
A.
4
B.
6
C.
3
D.
2

Answers

Answer:

the answer gonna be 3

Answer: I the answer is 3 100%

Step-by-step explanation: I took the test

3.294e6 standard form

Answers

Answer:

3.294

Step-by-step explanation:

Which function is continuous at x = –4?

Answers

Answer:

The correct answer is C. I tried B and got it wrong

Step-by-step explanation:

Find mean & margin of error if 28.4 < µ < 38.8

Answers

Answer:

The mean is of 33.6

The margin of error is of 5.2.

Step-by-step explanation:

Confidence interval concepts:

A confidence interval has two bounds, a lower bound and an upper bound.

A confidence interval is symmetric, which means that the point estimate used is the mid point between these two bounds, that is, the mean of the two bounds.

In this question:

Lower bound: 28.4

Upper bound: 38.8

Mean

(28.4+38.8)/2 = 33.6.

The mean is of 33.6

Margin of error:

(38.8 - 28.4)/2 = 5.2

The margin of error is of 5.2.

Help please I’ll give extra points and brainlist

Answers

Answer:

Step-by-step explanation:

Probably D,  he's measuring voltage across the wire.. and then across the light bulb,   there would be very little across the wire and a lot across the light bulb

A rectangular pool is being constructed with a length that is four times the width. There will be a walkway constructed around the pool that is 6 feet wide all around. Write a factored expression for the area in square feet of the pool and the walkway combined.

Answers

Answer:

(4x²+36) feet²

Step-by-step explanation:

Area of the pool = L × W

Take width as x and Length as 4x

4x × x = (4x²)feet² {area of pool}

Area of walkway = L × W

6 × 6 = 36feet²

Total area = 4x² + 36 feet²

Will give the brainliest answer and 20 points to anyone who can give a complete answer and not a scam link or a joke answer or begging for points (those 3 types of answers will be reported)

Courtney and Christy both leave the coffee shop at the same time, but in opposite directions. If Christy travels 9 mph faster than Courtney and after 7 hours they are 189 miles apart, how fast is each traveling?

Courtney is traveling ___________ mph.

Christy is traveling _____________ mph.

Answers

Answer:

Courtney is travelling at 9mph

Christy is travelling at 18mph

Step-by-step explanation:

Courtney's speed = x

Christy's speed = y

Christy travels 9 mph faster than Courtney: x+9=y

Distance = speed * time

Courtney's distance after 7 hours = 7x

Christy's distance after 7 hours = 7y

After 7 hours, they're 189 miles apart:

7x+7y=189

x+y=27

x+y=27

x+x+9=27

2x=18

x=9

y=x+9

y=9+9

y=18

Find all the missing elements : C=120degrees
b= 5
c=11

Answers

Answer:

A = 36.8°

B = 23.2°

a = 7.6

Step-by-step explanation:

Given:

C = 120°

b = 5

c = 11

Required:

Find A, B, and a.

Solution:

✔️To find B, apply the Law of Sines

[tex] \frac{sin(B)}{b} = \frac{sin(C)}{c} [/tex]

Plug in the values

[tex] \frac{sin(B)}{5} = \frac{sin(120)}{11} [/tex]

Cross multiply

Sin(B)*11 = sin(120)*5

Divide both sides by 11

[tex] sin(B) = \frac{sin(120)*5}{11} [/tex]

[tex] sin(B) = \frac{sin(120)*5}{11} [/tex]

Sin(B) = 0.3936

B = [tex] sin^{-1}(0.3936) [/tex]

B = 23.1786882° ≈ 23.2° (nearest tenth)

✔️Find A:

A = 180° - (B + C) (sum of triangle)

A = 180° - (23.2° + 120°)

A = 36.8°

✔️To find a, apply the Law of sines:

[tex] \frac{sin(A)}{a} = \frac{sin(B)}{b} [/tex]

Plug in the values

[tex] \frac{sin(36.8)}{a} = \frac{sin(23.2)}{5} [/tex]

Cross multiply

a*sin(23.2) = 5*sin(36.8)

Divide both sides by sin(23.2)

[tex] a = \frac{5*sin(36.8)}{sin(23.2) [/tex]

a = 7.60294329 ≈ 7.6 (nearest tenth)

The dot plots show the numbers of children’s books purchased by customers at two different bookstores on one day.

Which statement is supported by the information in the dot plots?


A) The mean of the data for Store 1 is greater than the mean of the data for Store2
B) The mode of the data for Store 2 is greater than the mode of the data for Store1
C) The median of the data for Store 2 is greater than the median of the data for Store1
D) The range of the data for Store 1 is greater than the range of the data for Store2

Answers

Answer:

A

Step-by-step explanation:

since mean is the most annoying to calculate I went through and did everything else, the range is the same as both charts go 0-6. The median is is the middle number which means store 1 has a higher number of 3' s but our option says store 2 is greater and B is the mode, the number that shows up the most.

Can someone help me with this problem please. ( I need it as fast as possible).

Answers

Answer:

D-B-A-C

Step-by-step explanation:

ted is twice his sister's age and three years younger than joe. ted's sister is half of a century plus ten. how old is ted how old is ted's sister​

Answers

Answer:

120, 60

Step-by-step explanation:

half a century = 60 + 10 x 2 = ted.

she is 60.

Solve for x:
2x + 9 = 3

Answers

Answer:

x = -3

Step-by-step explanation:

2x + 9 = 3

2x = 3 - 9

2x = -6

x = -3

Answer:

- 3

Step-by-step explanation:

given

2x + 9 = 3

2x = 3 - 9

2x = - 6

x = - 6/2

x = - 3

hope it helps :)

Will give brainliest

Answers

Answer: Because the question uses the word “distinct” meaning obvious, and clear, I would select AB, AC, CB. (If it’s asking for all the possible line segments, I would select AB, AC, CB, BA, CA, BC).

A quarter has a diameter of 24 mm.
Which measurement is closest to the
circumference of the quarter in
millimeters?
A. 452.39 mm
B. 37.7 mm
C. 75.4 mm
D. 150.8 mm

Answers

Answer:

C or D

Step-by-step explanation:

The groundhog population of​ Punxsutawny, Pennsylvania is closely monitored each year. Two years ago the population decreased by​ 12%. Last year the number of groundhogs increased by​ 6%. This year the population also increased by​ 9%. What was the percentage​ increase/decrease of groundhogs over these three​ years? Round your answer to the nearest tenth of a percentage poin

Answers

Answer:

There was a increase of 1.7% over these three​ years

Step-by-step explanation:

Multipliers:

For a decrease of a%, we multiply by: [tex]\frac{100-a}{100}[/tex]

For a increase of a%, we multiply by: [tex]\frac{100+a}{100}[/tex]

What was the percentage​ increase/decrease of groundhogs over these three​ years?

Decrease of 12%(multiplication by 0.88).

Increase of 6%(multiplication by 1.06).

Increase of 9%(multiplication by 1.09).

After these three years:

0.88*1.06*1.09 = 1.017

1.017 - 1 = 0.017

0.017*100% = 1.7%

There was a increase of 1.7% over these three​ years

What do those emojis mean in words?

Answers

Dark barking up no tree?

A black hole

The last one ...a girl playing a instrument

Find the Perimeter of this figure. I do y get it

Answers

Answer:

56m

Step-by-step explanation:

5+7+5+11+7+16+5

= 56

Well to find the perimeter of any shape all you have to do is add the lengths of all the sides. In this problem the lengths of the sides are 5 + 5 + 5 + 11 + 7 + 16 + 7 which equals 56. So the perimeter of this shape is 56 m. Hope this helps!

simplify 3 times x² times y times 4z times x times 2y times z​

Answers

Answer:

3(x^2 x Y)(4z x X)(2y x Z)

Step-by-step explanation:

Answer:

[tex]3(x^{3} * 2y^2*4z^2)[/tex]

Step-by-step explanation:

x^2(x) = x^3

2y(y) = 2y^2

4z(z) = 4z^3

Multiple it all by 3

The management of KSmall Industries is considering a new method of assembling a computer. The current assembling method requires a mean time of 66 minutes with a standard deviation of 3.0 minutes. Using the new method, the mean assembly time for a random sample of 24 computers was 61 minutes.
a. Using the 0.10 level of significance, can we conclude that the assembly time using the new method is faster?
b. What is the probability of a Type II error? (Round "Critical values" to 2 decimal places and round your final answer to 4 decimal places.)

Answers

Answer:

Part a:

Since the calculated z= 8.1649 falls in the critical region  z < ± 1.28 we reject H0 and conclude that the assembly time using the new method is faster.

Part b:

P (Type II Error)=  0.6628

Step-by-step explanation:

The null and alternate hypothesis are

H0: μ1 ≥ μ2   against the claim Ha: μ1 < μ2

This is left tailed test

The critical region for this test at 0.10 ∝ is z < ± 1.28

The test statistic

z= x1-x2/ s/√n

z= 66-61/ 3/√24

z= 5/0.61238

z= 8.16486

Since the calculated z= 8.1649 falls in the critical region  z < ± 1.28 we reject H0 and conclude that the assembly time using the new method is faster.

Part b:

P (Type II Error)  = P ( accept H0/ H0 is false)

z ( ∝)= X-u/s/√n

1.28= X-61/0.61238

X= 61.7838

So I will incorrectly fail to reject the null as long as a draw a sample mean that greater than 61.7838

 The probability of a Type II error is given by

P (z> 61.7838-66/24)

P (z>- 0.42161)

From the tables

P (z>- 0.42161)=  0.6628

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