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3 years ago

Can someone help me with this question and explain it to me please 2x^2-19x+24=0

2 answers:

6 0

This is a quadratic function and the object is to solve for x. There are several methods to do this so depends on what type of lesson you are learning in order to know which method you should use. Would be pretty tough to factor since there are so many possibilities for 24, but you could easily use quadratic formula where a=2, b=-19, and c=24. You could also use complete the square, but would need to divide everything by 2 first, leaving you a fraction i the middle so quadratic formula would be the easiest.

vodomira [7]3 years ago

4 0

Do you have to use the quadratic formula?

You might be interested in

Stacy sells art prints for $12 each. Her expenses are $2.50 per print, plus $38 for equipment. How many prints must she sell for

charle [14.2K]

4 prints
12x = 2.5x + 38
at 4, these expressions are equal

7 0

3 years ago

Lie detectors Refer to Exercise 82. Let Y = the number of people who the lie detector says are telling the truth.

mr_godi [17]

Answer:

a) $P(Y\geq 10) = PX \leq 2) = 0.558$

b) $E(X) = \mu_X = np = 12*0.2 = 2.4$

$\sigma_X = \sqrt{np(1-p)}=\sqrt{12*0.2*(1-0.2)}=1.386$

$E(Y) = \mu_Y = np = 12*0.8 = 9.6$

$\sigma_Y = \sqrt{np(1-p)}=\sqrt{12*0.8*(1-0.8)}=1.386$

For this case the expected value of people lying is 2.4 and the complement is 9.6 and that makes sense since we have a total of 12 poeple.

And the deviation for both variables are the same.

Step-by-step explanation:

Assuming this previous info : "A federal report finds that lie detector tests given to truthful persons have probability about 0.2 of suggesting that the person is deceptive. A company asks 12 job applicants about thefts from previous employers, using a lie detector to assess their truthfulness. Suppose that all 12 answer truthfully. Let X = the number of people who the lie detector says are being deceptive"

For this case the distribution of X is binomial $X \sim N(n=12, p=0.2)And we define the new random variable Y="the number of people who the lie detector says are telling the truth" so as we can see y is the oppose of the random variable X, and the distribution for Y would be given by:[tex] Y \sim Bin (n=12,p=1-0.2=0.8)$

The binomial distribution is a "DISCRETE probability distribution that summarizes the probability that a value will take one of two independent values under a given set of parameters. The assumptions for the binomial distribution are that there is only one outcome for each trial, each trial has the same probability of success, and each trial is mutually exclusive, or independent of each other".

The probability mass function for the Binomial distribution is given as:

$P(X)=(nCx)(p)^x (1-p)^{n-x}$

Where (nCx) means combinatory and it's given by this formula:

$nCx=\frac{n!}{(n-x)! x!}$

Part a

For this case we want to find this probability:

$P(Y \geq 10) = P(Y=10)+P(Y=11) +P(Y=12)$

And if we find the individual probabilites we got:

$P(Y=10)=(12C10)(0.8)^{10} (1-0.8)^{12-10}=0.283$

$P(Y=11)=(12C11)(0.8)^{11} (1-0.8)^{12-11}=0.206$

$P(Y=12)=(12C12)(0.8)^{12} (1-0.8)^{12-12}=0.069$

And if we replace we got:

$P(Y \geq 10) =0.283+0.206+0.069=0.558$

And for this case if we find $P(X\leq 2)=P(X=0) +P(X=1)+P(X=2)$ for the individual probabilites we got:

$P(X=0)=(12C0)(0.2)^0 (1-0.2)^{12-0}=0.069$

$P(X=1)=(12C1)(0.2)^1 (1-0.2)^{12-1}=0.206$

$P(X=2)=(12C2)(0.2)^2 (1-0.2)^{12-2}=0.283$

$P(X\leq 2)=0.283+0.206+0.069=0.558$

So as we can see we have $P(Y\geq 10) = P(X \leq 2) = 0.558$

Part b

Random variable X

For this case the expected value is given by:

$E(X) = \mu_X = np = 12*0.2 = 2.4$

And the deviation is given by:

$\sigma_X = \sqrt{np(1-p)}=\sqrt{12*0.2*(1-0.2)}=1.386$

Random variable Y

For this case the expected value is given by:

$E(Y) = \mu_Y = np = 12*0.8 = 9.6$

And the deviation is given by:

$\sigma_Y = \sqrt{np(1-p)}=\sqrt{12*0.8*(1-0.8)}=1.386$

For this case the expected value of people lying is 2.4 and the complement is 9.6 and that makes sense since we have a total of 12 poeple.

And the deviation for both variables are the same.

8 0

3 years ago

It was Robin's birthday and she knew she was going to have a good day. She was driving to work, and when she turned on the radio

Andreas93 [3]

Answer:

1.Random circumstance: Color of traffic light when Robin approaches the main intersection. Possible outcomes: Traffic light is green when Robin arrives, or Traffic light is not green when Robin arrives.

2.Random circumstance: Song on the radio when first turned on. Possible outcomes: Robin's favorite song is playing, or Robin's favorite song is not playing.

4.Random circumstance: Nearest available parking space. Possible outcomes: Robin finds an empty parking space in front of the building, or Robin does not find an empty parking space in front of the building.

Step-by-step explanation:

A random circumstance is one whose outcome cannot be predicted because we either do not have the full details of the matter or it has not been confirmed yet by a reliable source. In the short description of events provided above;

1.The color of the traffic light is unpredictable because it is not under the control of the drivers but is automated.

2. Robin's favorite song playing on the radio is a random circumstance because she has no control over what song is played. So, she might as well have tuned in and it would be her least favorite song playing.

3. Robin driving into the office and finding the parking space empty is a random circumstance because it is not predictable. She might have come in and found the entire space filled.

7 0

3 years ago

Find the area bounded by y=ln x, x=2, x=4 and the x-axis.

Advocard [28]

4 sq.units

area of a rectangle = length × breadth

length = 4units

breadth = 1units

A = l × b

= 4 × 1

= 4 sq.units

<h3>HOPE IT HELPS U </h3>

IF YES 

MARK ME AS THE BRAINLIEST

8 0

4 years ago

PLEASE HELP NEED HELP ASAP

Ivahew [28]

10)
200 / 5 = 40

answer
p >= 40

11)
$15 per hour
so
15p >= 200
solve for p

p >= 200/15
p >= 13.33 or p?= 13 1/3

minimum hours = 13.33 or 13 1/3

8 0

4 years ago