Why is a 99 confidence interval wider than a 95 confidence interval?

Solve the simultaneous equation y-2x+1=0 and 4x^2+3y^2-2xy=7

Lapatulllka [165]

The first equation is $y-2x+1=0$

$y=2x-1$ (Equation 1)

The second equation is $4x^{2}+3y^{2}-2xy=7$ (Equation 2)

Putting the value of x from equation 1 in equation 2.

we get,

$4x^{2}+3(2x-1)^{2}-2x(2x-1)=7$

$4x^{2}+3(4x^{2}+1-4x)-4x^{2}+2x=7$

by simplifying the given equation,

$12x^{2}-10x-4=0$

$6x^{2}-5x-2=0$

Using discriminant formula,

$D=b^{2}-4ac$

$D=25-4 \times 6 \times -2 = 73$

Now the formula for solution 'x' of quadratic equation is given by:

$x=\frac{-b+\sqrt{D}}{2a} and x=\frac{-b-\sqrt{D}}{2a}$

$x=\frac{5+\sqrt{73}}{12} and x=\frac{5-\sqrt{73}}{12}$

Hence, these are the required solutions.

8 0

2 years ago

Which ordered pair can be plotted together with these four points, so that the resulting graph still represents a function?

MrRissso [65]

Answer:

B.(-1,2)

Step-by-step explanation:

In a function, there can not be two different values of y corresponding to the same value of x.

See the graph attached.

Here, the points on the graph are (1,2), (2,-3), (-2,-2) and (-3,1).

If we consider point (-2,2) then there will be two points corresponding to the same x value i.e. (-2,-2) and (-2,2).

Similarly, if we consider the point (2,-2) or (2.-1) then also there becomes more than one values of y for a single value of x i.e. x = 2.

So, if we consider the ordered pair (-1,2) then only the graph still represents a function. (Answer)

7 0

2 years ago

Explain the term <br><img src="https://tex.z-dn.net/?f=%20%5Cmathbb%20%7B%5Cgreen%7Babolute%20%5C%3A%20%7B%20%5Cpink%7Bmeasure%7

Setler [38]

Answer:

<h2> abolute measure </h2>

it is quantity measured and same unit data and also as an original data it's is an original data expressed and unit of series

<h2>range </h2>

largest value difference to smallest value in data

<h2>Quartiles </h2>

it is an semi and half of range

also as arithmetic mean as more deviation of range

3 0

1 year ago

The mean amount spent by a family of four on food per month is $500 with a standard deviation of $75. Assuming that the food cos

JulijaS [17]

Answer:

The probability that a family spends less than $410 per month

P( X < 410) = 0.1151

Step-by-step explanation:

<em>Given mean of the population = 500 </em>

<em>Given standard deviation of the Population = 75</em>

Let 'X' be the variable in normal distribution

$Z = \frac{x-mean}{S.D}$

<em>Given X = $410</em>

The probability that a family spends less than $410 per month

P( X < 410) = P( Z < - 1.2 )

= 0.5 - A( -1.2)

= 0.5 - A(1.2)

= 0.5 - 0.3849 ( ∵from normal table)

= 0.1151

<u>Final answer:-</u>

The probability that a family spends less than $410 per month

P( X < 410) = 0.1151

6 0

2 years ago

$250, 2.85%, 3 years

Lerok [7]

So then what is the question?

7 0

3 years ago