All categories

3 years ago

Is 15 + k an equation? answer please

Mathematics

1 answer:

expeople1 [14]3 years ago

3 0

Answer:

No, I don't think so; an equation must have an equal sign in it. Expressions, however, do not have equal signs in them. Therefore I think 15 + k is an <em>expression</em>, not an equation. Hope this helps :)

You might be interested in

A professor of women's studies is interested in determining if stress affects the menstrual cycle. Ten women are randomly sample

BabaBlast [244]

Answer:

Null hypothesis: $\mu_1 = \mu_2$

Alternative hypothesis: $\mu_1 \neq \mu_2$

$t=\frac{(20.4 -27.6)-(0)}{\sqrt{\frac{2.074^2}{5}}+\frac{2.702^2}{5}}=-4.73$

$df=5+5-2=8$

$t_{crit}=\pm 2.306$

Reject H0: stress affects the menstrual cycle

Step-by-step explanation:

The statistic is given by the following formula:

$t=\frac{(\bar X_1 -\bar X_2)-(\mu_{1}-\mu_2)}{\sqrt{\frac{s^2_1}{n_1}}+\frac{s^2_2}{n_2}}$

Where t follows a t distribution with $n_1+n_2 -2$ degrees of freedom

The system of hypothesis on this case are:

Null hypothesis: $\mu_1 = \mu_2$

Alternative hypothesis: $\mu_1 \neq \mu_2$

Or equivalently:

Null hypothesis: $\mu_1 - \mu_2 = 0$

Alternative hypothesis: $\mu_1 -\mu_2 \neq 0$

Our notation on this case :

$n_1 =5$ represent the sample size for group 1

$n_2 =2$ represent the sample size for group 2

Tha data given is:

Group 1 (High stress) : 20,23,18,19,22

Group 2 (Relatively stress free): 26,31,25,26,30

We can calculate the sample mean and the sample deviation with the following formulas:

$\bar X =\frac{\sum_{i=1}^n x_i}{n}$

$s=\sqrt{\frac{\sum_{i=1}^n (x_i -\bar X)^2}{n-1}}$

$\bar X_1 =20.4$ represent the sample mean for the group 1

$\bar X_2 =27.6$ represent the sample mean for the group 2

$s_1=2.074$ represent the sample standard deviation for group 1

$s_2=2.702$ represent the sample standard deviation for group 2

And now we can calculate the statistic:

$t=\frac{(20.4 -27.6)-(0)}{\sqrt{\frac{2.074^2}{5}}+\frac{2.702^2}{5}}=-4.73$

Now we can calculate the degrees of freedom given by:

$df=5+5-2=8$

Now we can calculate the critical value since the confidence is 95% the value for the significance would be $\alpha=1-0.95=0.05$ and the value for $\alpha/2 =0.025$ and if we find a critical value on th t distribution with 8 degrees of freedom that accumulates 0.025 of the area on each tail we got $t_{crit}=\pm 2.306$

Since our calculated value is lower than the critical value, we have enough evidence to reject the null hypothesis. And makes sense say that the difference between the two means are different at 5% of significance.

Reject H0: stress affects the menstrual cycle

5 0

3 years ago

22 meters per second in kilometers per hour.

lbvjy [14]

Answer:

79.2 kilometres per hour

Step-by-step explanation:

1 km = 1000 m

1 hr = 3600 sec. To convert km/hr into m/sec,

We multiply the speed which in this case is 22m/s

by 3.6 giving 79.2 kmh. Therefore 22m/s into kilometer is 79.2 kmh.

6 0

2 years ago

Read 2 more answers

Find the acute angle formed by line 2y=x+1

givi [52]

Answer:

26.57°

Step-by-step explanation:

$2y = x + 1 \\ y = \frac{1}{2} x + 1 \\ equating \: it \: with \\ y = mx + b \\ slope \: m = \frac{1}{2} \\ \because \: \tan \theta = m \\ \therefore \: \tan \theta = \frac{1}{2} = 0.5 \\ \therefore \: \theta = {tan}^{ - 1} (0.5) \\\therefore \: \theta = {tan}^{ - 1} ( \tan \: 26.565051177 \degree) \: \\ \\ \huge \red{ \boxed{\therefore \: \theta = 26.57 \degree}}$

6 0

3 years ago

Reed made a lasagna for dinner. That night, he ate1/4

Snezhnost [94]

Answer: 11/12

Step-by-step explanation:

First find the LCM of 4 and 3(12). Then make the denominator of both fractions 12(3/12 and 8/12). Then add the fractions to get that they ate 11/2 of the lasagna.

Hope it helps <3

6 0

4 years ago

How to find the measure of an exterior angle on a triangle

nexus9112 [7]

Hi there!

There are many ways to find the measure of an exterior angle of a triangle. I'll explain the easiest method to you. As you can see in the image, a line is drawn extending a side of the triangle. In order to find the measure of the exterior angle, we can subtract the measure of the adjacent interior angle from 180 (a straight angle). Doing this subtraction will give us the measure of the exterior angle.

Hope this helps!! :)

6 0

3 years ago

Read 2 more answers