Can someone please help ?!

Can someone help me please

zlopas [31]

Answer:

i cant see the picture

Step-by-step explanation:

7 0

3 years ago

Which statements about finding the area of the equilateral triangle are true? Check all that apply.

lara31 [8.8K]

Answer:

The correct options are 1, 2 and 4.

Step-by-step explanation:

The given triangle is an equilateral triangle. All the sides of an equilateral triangle are same. All interior angles are equal with measure 60 degree.

The distance from the center of an equilateral triangle to the midpoint of a side is known as apothem. In the given figure letter a represents the apothem.

Point D is the midpoint of BC,

$b=\frac{BC}{2}=\frac{8.7}{2}=4.35$

Use Pythagorean theorem in triangle COD. So, option 1 is correct.

$OC^2=OD^2+DC^2$

$5^2=a^2+(4.35)^2$

$25=a^2+18.9225$

$a=\pm 2.46526$

$a\approx\pm 2.5$

The distance can not be negative, so the length of the apothem is approximately 2.5 cm. Option 4 is correct.

The line OC bisects the angle C.

$tan(30^{\circ})=\frac{a}{b}$

$\frac{1}{\sqrt{3}=\frac{a}{4.35}$

$a\approx\pm 2.5$

Therefore option 2 is correct.

The perimeter of an equality triangle is

$P=3a=3(8.7)=26.1$

Option 3 is incorrect.

$A=\frac{\sqrt{3}}{4}a^2=\frac{\sqrt{3}}{4}(8.7)^2=32.77$

Option 5 is incorrect.

Therefore options 1, 2 and 4 are correct.

3 0

3 years ago

Read 2 more answers

According to data released by FiveThirty Eight (data drawn on Monday, August 17th, 2020), Donald Trump wins an Electoral College

sineoko [7]

Answer:

a) P = 0.274925

b) required confidence interval = (0.2705589, 0.2793344)

c) FALSE

d) FALSE

e) TRUE

f) There is still probability that he would win. And it would be highly unusual if he wins assuming that the true population proportion is 0.274925.

Step-by-step explanation:

a)

PROBABILITY

since total number of simulations is 40,000 and and number of times Donald Trump wins an Electoral College majority in the 2020 US Presidential Election is 10,997

so the required Probability will be 10,997 divided by 40,000

P = 10997 / 40000 = 0.274925

b)

To get 95% confidence interval for the parameter in question a

(using R)

>prop.test(10997,40000)

OUTPUT

1 - Sample proportion test with continuity correction

data: 10997 out of 40000, null probability 0.5

x-squared = 8104.5, df = 1, p-value < 2.23-16

alternative hypothesis : true p ≠ 0.5

0.2705589 0.2793344

sample estimate

p

0.274925

∴ required confidence interval = (0.2705589, 0.2793344)

c)

FALSE

This is a wrong interpretation of a confidence interval. It indicates that there is 95% chance that the confidence interval you calculated contains the true proportion. This is because when you perform several times, 95% of those intervals would contain the true proportion but as the confidence intervals will vary so you can't say that the true proportion is in any interval with 95% probability.

d)

FALSE

Once again, this is a wrong interpretation of a confidence interval. The confidence interval tells us about the population parameter and not the sample statistic.

e)

TRUE

This is a correct interpretation of a confidence interval. It indicates that if we perform sampling with same sample size (40000) several times and calculate the 95% confidence interval of population proportion for each of them, then 95% of these confidence interval should contain the population parameter.

f)

The simulation results obtained doesn't always comply with the true population. Also, result of one simulation can't be taken for granted. We need several simulations to come to a conclusion. So, we can never ever guarantee based on a simulation result to say that Donald Trump 'Won't' or 'Shouldn't' win.

There is still probability that he would win. And it would be highly unusual if he wins assuming that the true population proportion is 0.274925.

5 0

3 years ago

The measure of arc BCD is

makkiz [27]

Answer:

m∠BCD = 140°

Step-by-step explanation:

ABCD is cyclic quadrilateral. A property of cyclic quadrilateral states that the opposite angles of it sum up to 180°. Here:

m∠A + m∠C =180° and m∠B + m∠D = 180°

So, m∠A + m∠C =180°

m∠A = 40° (given in the question)

40° + m∠C = 180°

m∠C = 180° - 40° = 140°

∴m∠C = m∠BCD = 140°

6 0

3 years ago

In the reaction 2HgO(s) --> 2Hg(l) + O2(g) we measure the evolution of gas to determine the rate of reaction. At the beginnin

djverab [1.8K]

Answer:

0.034 L/min

Step-by-step explanation:

The rate of reaction is the volume change (ΔV) divided by the time(t) and divided by the coefficient of the compound in the reaction. The coefficient of O₂ is 1, so:

R = (0.36 - 0.02)/10

R = 0.034 L/min

4 0

3 years ago