-1+5/4x=-16 What number is x representing?

X^2-12x+12=0 completing the square

Makovka662 [10]

Answer:

x1 = 6 + 2√6 or x2 = 6 - 2√6

Step-by-step explanation:

x² - 12x + 12 = 0

We need to use formula:

a² - 2ab + b² = (a - b)².

x² - 12x = - 12

x² - 2*6x + 6²- 6² = - 12

(x - 6)² - 36 = -12

(x - 6)² = - 12 + 36

(x -6)² = 24

(x - 6) = √24 or (x-6) = -√24

(x - 6) = 2√6 or (x-6) = - 2√6

x = 6 + 2√6 or x = 6 - 2√6

3 0

3 years ago

Hey its my b day soon and i need my grade up plz help :)

frosja888 [35]

Answer:

it should be B.

Step-by-step explanation:

7 0

2 years ago

Please help me answer this question

avanturin [10]

By direct substitution and simplification, the trigonometric function z = cos (2 · x + 3 · y) represents a solution of the partial differential equation $\frac{\partial^{2} t}{\partial x^{2}} - \frac{\partial^{2} t}{\partial y^{2}} = 5\cdot z$ .

<h3>How to analyze a differential equation</h3>

Differential equations are expressions that involve derivatives. In this question we must prove that a given expression is a solution of a differential equation, that is, substituting the variables and see if the equivalence is conserved.

If we know that $z = \cos (2\cdot x + 3\cdot y)$ and $\frac{\partial^{2} t}{\partial x^{2}} - \frac{\partial^{2} t}{\partial y^{2}} = 5\cdot z$ , then we conclude that:

$\frac{\partial t}{\partial x} = -2\cdot \sin (2\cdot x + 3\cdot y)$

$\frac{\partial^{2} t}{\partial x^{2}} = - 4 \cdot \cos (2\cdot x + 3\cdot y)$

$\frac{\partial t}{\partial y} = - 3 \cdot \sin (2\cdot x + 3\cdot y)$

$\frac{\partial^{2} t}{\partial y^{2}} = - 9 \cdot \cos (2\cdot x + 3\cdot y)$

$- 4\cdot \cos (2\cdot x + 3\cdot y) + 9\cdot \cos (2\cdot x + 3\cdot y) = 5 \cdot \cos (2\cdot x + 3\cdot y) = 5\cdot z$

By direct substitution and simplification, the trigonometric function z = cos (2 · x + 3 · y) represents a solution of the partial differential equation $\frac{\partial^{2} t}{\partial x^{2}} - \frac{\partial^{2} t}{\partial y^{2}} = 5\cdot z$ .

To learn more on differential equations: brainly.com/question/14620493

#SPJ1

3 0

2 years ago

The circle has a radius of 11 cm. What is the area of the shaded sector? Use 3.14 for π, and round your answer to the nearest te

Temka [501]

379.9 cm 2 or 253 cm 2

3 0

2 years ago

The 2008 Workplace Productivity Survey, commissioned by LexisNexis and prepared by World One Research, included the question, "H

LenaWriter [7]

Answer:

A 95% confidence interval estimate of the mean number of hours a legal professional works on a typical workday is [7.44 hours, 10.56 hours].

Step-by-step explanation:

We are given that x is normally distributed with a known standard deviation of 12.6.

A sample of 250 legal professionals was surveyed, and the sample's mean response was 9 hours.

Firstly, the pivotal quantity for finding the confidence interval for the population mean is given by;

P.Q. = $\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }$ ~ N(0,1)

where, $\bar X$ = sample average mean response = 9 hours

$\sigma$ = population standard deviation = 12.6

n = sample of legal professionals = 250

$\mu$ = mean number of hours a legal professional works

Here for constructing a 95% confidence interval we have used One-sample z-test statistics as we know about population standard deviation.

So, 95% confidence interval for the population mean, $\mu$ is ;

P(-1.96 < N(0,1) < 1.96) = 0.95 {As the critical value of z at 2.5% level

of significance are -1.96 & 1.96}

P(-1.96 < $\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }$ < 1.96) = 0.95

P( $-1.96 \times {\frac{\sigma}{\sqrt{n} } }$ < ${\bar X-\mu}$ < $-1.96 \times {\frac{\sigma}{\sqrt{n} } }$ ) = 0.95

P( $\bar X-1.96 \times {\frac{\sigma}{\sqrt{n} } }$ < $\mu$ < $\bar X+1.96 \times {\frac{\sigma}{\sqrt{n} } }$ ) = 0.95

95% confidence interval for $\mu$ = [ $\bar X-1.96 \times {\frac{\sigma}{\sqrt{n} } }$ , $\bar X+1.96 \times {\frac{\sigma}{\sqrt{n} } }$ ]

= [ $9-1.96 \times {\frac{12.6}{\sqrt{250} } }$ , $9+1.96 \times {\frac{12.6}{\sqrt{250} } }$ ]

= [7.44 hours, 10.56 hours]

Therefore, a 95% confidence interval estimate of the mean number of hours a legal professional works on a typical workday is [7.44 hours, 10.56 hours].

5 0

3 years ago