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3 years ago

What is the equation of the directrix of the parabola given by the equation (y − 3)2 = 8(x − 5)?

1 answer:

8 0

The vertex of the parabola is at (5,3) and its focal length is 8/4 = 2.
Since it opens to the right, the directrix will be a vertical line 2 units to the left of the vertex, so its equation will be x=(5-2), or x=3

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What is 124 decreased by 67%

inysia [295]

Answer:

40.92

Step-by-step explanation:

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3 years ago

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A special liquid is held in a tank described as (x 2 + y 2 ) ≤ z ≤ 1 in a Cartesian coordinate system. Assume that the density o

vivado [14]

Since $\rho=\dfrac mV$ (density = mass/volume), we can get the mass/weight of the liquid by integrating the density $\rho(x,y,z)$ over the interior of the tank. This is done with the integral

$\displaystyle\int_{-1}^1\int_{-\sqrt{1-x^2}}^{\sqrt{1-x^2}}\int_{x^2+y^2}^1(2-z^2)\,\mathrm dz\,\mathrm dy\,\mathrm dx$

which is more readily computed in cylindrical coordinates as

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3 years ago

Does second-hand smoke increase the risk of a low birthweight? A baby is considered have low birthweight if he/she weighs less t

marishachu [46]

Answer:

Option 2) Null hypothesis: p = 0.078 , Alternate hypothesis: p > 0.078

Step-by-step explanation:

We are given the following in the question:

According to the National Center of Health Statistics, about 7.8% of all babies born in the U.S. are categorized as low birth weight.

Sample size, n = 1200

p = 7.8% = 0.078

We have to carry a hypothesis test whether national percentage is higher than 7.8% or not.

Thus, we can design the null and the alternate hypothesis

$H_{0}: p = 0.078\H_A: p > 0.078$

Thus, the correct answer is:

Option 2) Null hypothesis: p = 0.078 , Alternate hypothesis: p > 0.078

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3 years ago

A: Using this figure, B' is the of B. reflection prelmage dilation Image

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Answer:

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Step-by-step explanation:

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Nikita invests $2,000 into a bank account with a 4% annual interest rate. In seven years, which is the most expensive item she c

Stella [2.4K]

Answer:

Anything that does not cost more than $2,560.00

Step-by-step explanation:

Provided that Nikita is spending money that she had invested and the amount she collected over the period of 7 years. She can buy any item that costs no more than $2,560.00 but how?

It is a problem of simple interest:

Here the principal amount (P) = $2,000.00

Interest rate (r) = 4%

Time period (t) = 7 years

So, total amount that she would get by the end of 7 years is:

$A=P+SI$