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3 years ago

Need help now, will give brainliest

Mathematics

2 answers:

Elena-2011 [213]3 years ago

8 0

Answer:

really??

Step-by-step explanation:

zhenek [66]3 years ago

4 0

Answer:

sorry I don't understand it

You might be interested in

Evaluate the expression 2 . 14 x − 42 . 9 for x = 22 . 4 .

zepelin [54]

Step-by-step explanation:

2 . 14 x − 42 . 9 for x = 22 . 4 .

2.14(22.4) = 47.936
47.936-42.9 = 5.036

your answer is 5.036

5 0

3 years ago

You and your friend collect each rocks and fossils. your friend collects three times as many rocks and half as many fossils as y

Murljashka [212]

Answer:

you - 4 rocks and 16 fossils
friend - 12 rocks and 8 fossils

Step-by-step explanation:

Let the rock be r and the fossil be f

Equations

You: r + f = 20
Friend: 3r + 1/2f = 20

Double the second equation and subtract the first one:

2(3r + 1/2f) - (r - f) = 2*20 - 20
6r - r = 20
5r = 20
r = 4

Then find f:

f = 20 - 4 = 16

So you collect 4 rocks and 16 fossils

Friend collects:

4*3 = 12 rocks and
1/2*16 = 8 fossils

8 0

3 years ago

Can someone help me with these 4 questions

olya-2409 [2.1K]

15. 145. 360-90-95-30
16. 90

The other picture number 16 again I already did that one.

4 0

4 years ago

Write the equation of the parabola that has its x-intercepts at (1+<img src="https://tex.z-dn.net/?f=%5Csqrt%7B5%7D" id="TexForm

VladimirAG [237]

Answer:

$y=2x^2-4x-8$

Step-by-step explanation:

Factored form of a parabola

$y=a(x-p)(x-q)$

where:

p and q are the x-intercepts.
a is some constant.

Given x-intercepts:

(1+√5, 0)
(1-√5, 0)

Therefore:

$\implies y=a(x-(1+\sqrt{5}))(x-(1-\sqrt{5}))$

$\implies y=a(x-1-\sqrt{5})(x-1+\sqrt{5})$

To find a, substitute the given point (4, 8) into the equation and solve for a:

$\implies a(4-1-\sqrt{5})(4-1+\sqrt{5})=8$

$\implies a(3-\sqrt{5})(3+\sqrt{5})=8$

$\implies4a=8$

$\implies a=2$

Therefore, the equation of the parabola in factored form is:

$\implies y=2(x-1-\sqrt{5})(x-1+\sqrt{5})$

Expand so that the equation is in standard form:

$\implies y=2(x^2-x+\sqrt{5}x-x+1-\sqrt{5}-\sqrt{5}x+\sqrt{5}-5)$

$\implies y=2(x^2-x-x+\sqrt{5}x-\sqrt{5}x+\sqrt{5}-\sqrt{5}+1-5)$

$\implies y=2(x^2-2x-4)$

$\implies y=2x^2-4x-8$

6 0

2 years ago

A health statistics agency in a certain country tracks the number of adults who have health insurance. Suppose according to the

Nana76 [90]

Answer:

a) There is a 15.3% probability that a randomly selected person in this country is 65 or older.

b) Given that a person in this country is uninsured, there is a 2.2% probability that the person is 65 or older.

Step-by-step explanation:

We have these following percentages:

5.3% of those under the age of 18, 12.6% of those ages 18–64, and 1.3% of those 65 and older do not have health insurance.

22.6% of people in the county are under age 18, and 62.1% are ages 18–64.

(a) What is the probability that a randomly selected person in this country is 65 or older?

22.6% are under 18

62.10% are 18-64

The rest are above 65

100% - (22.6% + 62.10%) = 15.3%

There is a 15.3% probability that a randomly selected person in this country is 65 or older.

b) Given that a person in this country is uninsured, what is the probability that the person is 65 or older?

This can be formulated as the following problem:

What is the probability of B happening, knowing that A has happened.

It can be calculated by the following formula

$P = \frac{P(B).P(A/B)}{P(A)}$

Where P(B) is the probability of B happening, P(A/B) is the probability of A happening knowing that B happened and P(A) is the probability of A happening.

So, what is the probability that a person is 65 and older, given that the person is uninsured.

P(B) is the probability that a person is 65 and older. From a), we have that $P(B) = 0.153$

P(A/B) is the probability is uninsured, given that that person is 65 and older. So $P(A/B) = 0.013$

P(A) is the probability that a person is uninsured. That is the sum of 5.3% of 22.6%, 12.6% of 62.1% and 1.3% of 15.3%. So:

$P(A) = 0.053*(0.226) + 0.126*(0.621) + 0.013*(0.153) = 0.0922$

$P = \frac{P(B).P(A/B)}{P(A)} = \frac{0.153*0.013}{0.0922} = 0.022$

Given that a person in this country is uninsured, there is a 2.2% probability that the person is 65 or older.

6 0

3 years ago