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3 years ago

I Need Help With This One

Mathematics

1 answer:

Arisa [49]3 years ago

7 0

Answer:

x = -6 x= -3

Step-by-step explanation:

f(x) = x^2+9x+18

Set equal to 0 to find the zeros

0 = x^2+9x+18

Factor, what numbers multiply to 18 and add to 9

6*3 =18

6+3=9

0= (x+6) (x+3)

Using the zero product property

x+6 =0 x+3 =0

x = -6 x= -3

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F(x)=1+log4^x the 4 is low to the log

SVEN [57.7K]

Well, if you subtract one you get -1=log4^x. base four on each side: 4(to the power of negative 1)=4(to the power of log base four) x. Four to the power of log base 4 cancels, and you're left with 4 to the power of -1=x. the negative exponent recipricates, so x=1/4. you're welcome.

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3 years ago

Which of these numbers is conposite? 4,7,23,29,41

zhenek [66]

The composite is 4 .

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Turtle14526

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3 years ago

Solve by substitution. 5x-3y=-4 x+y=-4

GrogVix [38]

Answer:

x=-2,y=-2

Step-by-step explanation:

x+y=-4

x=-4-y--(3)

substitute (3) in (1)

5(-4-y) -3y=-4

-20-5y-3y=-4

-8y=16

y=16/-8

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5 0

3 years ago

Assume the random variable X is normally distributed with mean 53 and standard deviation of 6. Find the 9th percentile

satela [25.4K]

Answer:

The 9th percentile of X is 44.96

Step-by-step explanation:

Percentiles for a Normal Distribution

The standard normal distribution can be used for computing percentiles. For example, the median is the 50th percentile being the center value, the first quartile is the 25th percentile, and so on.

To compute percentiles of a normal distribution we can use the formula

$X=\mu+z\sigma$

Where $\mu$ is the mean, $\sigma$ is the standard deviation of the variable X, and z is the z-score value from the standard tables

The value of X can also be directly obtained from digital tables included in math packages and tools like Excel.

The Excel NORM.INV Function calculates the inverse of the cumulative Normal Distribution Function for a given value of p, $\mu$ and $\sigma$ .

We'll use the values

$p=9\%=0.09,\ \mu=53, \ \sigma=6$

NORM.INV(0.09,53,6) results in 44.96 which means the 9th percentile of X is 44.96

We could have used the standard normal distribution, which only needs the value of p

$NORM.S.INV( 0.09 )=-1.34$

That is the value of z, we now apply the formula

$X=\mu+z\sigma$

$X=53+(-1.34)\cdot 6=44.96$

We get the very same result as before

6 0

3 years ago

I need help as soon as possible

bixtya [17]

I believe the correct answer is -2

7 0

3 years ago