5

Slope of 4/5, a width of 30…what is the height..?

maw [93]

$\qquad\qquad\huge\underline{{\sf Answer}}$

Here we go ~

Slope of the graph can be expressed as :

$\qquad \sf \dashrightarrow \:slope = \tan( \theta) = \dfrac{4}{5}$

$\qquad \sf \dashrightarrow \: \dfrac{x}{30} = \dfrac{4}{5}$

$\qquad \sf \dashrightarrow \: x = \dfrac{4}{5} \times 30$

$\qquad \sf \dashrightarrow \: x = {4}{} \times 6$

$\qquad \sf \dashrightarrow \: x = 24 \: units$

So, the value of x is 24 units

8 0

2 years ago

The length of the line segment containing the points (1,7) and (5,5)

ArbitrLikvidat [17]

Answer:

True

Step-by-step explanation:

Let A denotes the point (1,7)

Let B denotes the point (5,5)

We are supposed to find The length of the line segment containing the points

Formula : $d = \sqrt{(x_2-x_1)^2+(y_2-y_1)^2}$

$(x_1,y_1)=(1,7)\\(x_2,y_2)=(5,5)\\ d = \sqrt{(5-1)^2+(5-7)^2}\\ d = \sqrt{4^2+(-2)^2}\\ d = \sqrt{4^2+(-2)^2}\\d=4.47$

So,The length of the line segment containing the points (1,7) and (5,5) is 4.47 units is true.

Hence Option A is true

4 0

3 years ago

In a random sample of 80 teenagers, the average number of texts handled in a day is 50. The 96% confidence interval for the mean

Nastasia [14]

Answer:

a) $\bar X =\frac{46+54}{2}=50$

And the margin of error is given by:

$ME= \frac{54-46}{2}= 4$

The confidence level is 0.96 and the significance level is $\alpha=1-0.96=0.04$ and the value of $\alpha/2 =0.02$ and the margin of error is given by:

$ME=z_{\alpha/2}\frac{\sigma}{\sqrt{n}}$

We can calculate the critical value and we got:

$z_{\alpha/2} = 2.05$

And if we solve for the deviation like this:

$\sigma = ME * \frac{\sqrt{n}}{z_{\alpha/2}}$

And replacing we got:

$\sigma =4 *\frac{\sqrt{80}}{2.05} =17.45$

b) $ME=z_{\alpha/2}\frac{\sigma}{\sqrt{n}}=2.05 *\frac{17.45}{\sqrt{160}}=2.828$

And as we can see that the margin of error would be lower than the original value of 4, the margin of error would be reduced by a factor $\sqrt{2}$

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

$\bar X$ represent the sample mean

$\mu$ population mean (variable of interest)

$\sigma$ represent the population standard deviation

n=80 represent the sample size

Solution to the problem

Part a

The confidence interval for the mean is given by the following formula:

$\bar X \pm z_{\alpha/2}\frac{\sigma}{\sqrt{n}}$ (1)

For this case we can calculate the mean like this:

$\bar X =\frac{46+54}{2}=50$

And the margin of error is given by:

$ME= \frac{54-46}{2}= 4$

The confidence level is 0.96 and the significance level is $\alpha=1-0.96=0.04$ and the value of $\alpha/2 =0.02$ and the margin of error is given by:

$ME=z_{\alpha/2}\frac{\sigma}{\sqrt{n}}$

We can calculate the critical value and we got:

$z_{\alpha/2} = 2.05$

And if we solve for the deviation like this:

$\sigma = ME * \frac{\sqrt{n}}{z_{\alpha/2}}$

And replacing we got:

$\sigma =4 *\frac{\sqrt{80}}{2.05} =17.45$

Part b

For this case is the sample size is doubled the margin of error would be:

$ME=z_{\alpha/2}\frac{\sigma}{\sqrt{n}}=2.05 *\frac{17.45}{\sqrt{160}}=2.828$

And as we can see that the margin of error would be lower than the original value of 4, the margin of error would be reduced by a factor $\sqrt{2}$

5 0

3 years ago

Does the line represented by the equation: y=-2x+5 have a positive slope?

Veronika [31]

Answer:

Step-by-step explanation:

No, it doesn’t have a positive slope because the negative sign in front 2 means that the slope is negative and going down. If the slope would’ve been positive than there wouldn’t have been a negative sign and it would go up.

7 0

3 years ago

For the trinomial x2 + 10x + 21, we want to find two binomial factors

ratelena [41]

X^2 + 10X + 21

(X + 3)(X + 7)

7 0

3 years ago