Combine the like terms to create an equivalent expression: 5n + 6 +(-7n)

A parallelogram has symmetry with respect to the line that _____.

adelina 88 [10]

A parallelogram has symmetry wii respect to the line that C- Bisects it from opposite vertices.
All the others are never true for a parallelogram. You can try cutting out a parallelogram and folding it to see for yourself!
Hope this helps!!

4 0

3 years ago

Read 2 more answers

Is x/10=y a direct variation. If so, what is the constant of proportionality?

stiv31 [10]

Answer:

Yes,

y

=

−

x

10

is a direct variation

6 0

3 years ago

A circle is translated 4 units to the right and then reflected over the x-axis. Complete the statement so that it will always be

irga5000 [103]

Answer:

The statement is now presented as:

$\exists\, (h,k)\in \mathbb{R}^{2} /f: (x-h^{2})+(y-k)^{2}=r^{2}\implies f': [x-(h+4)]^{2}+[y-(-k)]^{2} = r^{2}$

In other words, this mathematical statement can be translated as:

There is a point (h, k) in the set of real ordered pairs so that a circumference centered at (h,k) and with a radius r implies a equivalent circumference centered at (h+4,-k) and with a radius r.

Step-by-step explanation:

Let $C = (h,k)$ the coordinates of the center of the circle, which must be transformed into $C'=(h', k')$ by operations of translation and reflection. From Analytical Geometry we understand that circles are represented by the following equation:

$(x-h)^{2}+(y-k)^{2} = r^{2}$

Where $r$ is the radius of the circle, which remains unchanged in every operation.

Now we proceed to describe the series of operations:

1) Center of the circle is translated 4 units to the right (+x direction):

$C''(x,y) = C(x, y) + U(x,y)$ (Eq. 1)

Where $U(x,y)$ is the translation vector, dimensionless.

If we know that $C(x, y) = (h,k)$ and $U(x,y) = (4, 0)$ , then:

$C''(x,y) = (h,k)+(4,0)$

$C''(x,y) =(h+4,k)$

2) Reflection over the x-axis:

$C'(x,y) = O(x,y) - [C''(x,y)-O(x,y)]$ (Eq. 2)

Where $O(x,y)$ is the reflection point, dimensionless.

If we know that $O(x,y) = (h+4,0)$ and $C''(x,y) =(h+4,k)$ , the new point is:

$C'(x,y) = (h+4,0)-[(h+4,k)-(h+4,0)]$

$C'(x,y) = (h+4, 0)-(0,k)$

$C'(x,y) = (h+4, -k)$

And thus, $h' = h+4$ and $k' = -k$ . The statement is now presented as:

$\exists\, (h,k)\in \mathbb{R}^{2} /f: (x-h^{2})+(y-k)^{2}=r^{2}\implies f': [x-(h+4)]^{2}+[y-(-k)]^{2} = r^{2}$

In other words, this mathematical statement can be translated as:

There is a point (h, k) in the set of real ordered pairs so that a circumference centered at (h,k) and with a radius r implies a equivalent circumference centered at (h+4,-k) and with a radius r.

4 0

3 years ago

Grades on a standardized test are known to have a mean of 1000 for students in the United States. The test is administered to 45

krok68 [10]

Answer:

a

The 95% confidence interval is $1003 < \mu$

b

Yes there is statistically significant evidence that students in Florida perform differently from other students in the United States

Step-by-step explanation:

From the question we are told that

The population mean is $\mu = 1000$

The sample size is $n = 453$

The sample mean is $\= x = 1013$

The standard deviation is $s = 108$

Given that the confidence level is 95% then the level of significance is mathematically represented as

$\alpha = 100 - 95$

=> $\alpha = 5\%$

=> $\alpha = 0.05$

The critical value for $\frac{\alpha }{2}$ obtained from the normal distribution table is

$Z_{\frac{\alpha }{2} } = 1.96$

Generally the margin of error is mathematically represented as

$E = Z_{\frac{\alpha }{2} } * \frac{s}{\sqrt{n} }$

=> $E = 1.96 * \frac{108}{\sqrt{453} }$

=> $E = 9.946$

Generally the 95% confidence interval is mathematically represented as

$\= x - E < \mu < \= x + E$

=> $1013 - 9.946 < \mu < 1013 + 9.946$

=> $1003 < \mu$

Given that the population mean(1000) is not within the 95% confidence interval for l for the average test score for students in Florida, then it means that there is statistically significant evidence that students in Florida perform differently from other students in the United States

4 0

3 years ago

CAN ANYONE TELL ME WHAT THE ANWSER IS:

Anna71 [15]

2.8 I got that same on on khan academy it’s 2.8 trust me

7 0

3 years ago

Combine the like terms to create an equivalent expression: 5n + 6 +(-7n) - 9