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1 year ago

12

An atom of a certain element has 21 protons, 21

1 answer:

Lorico [155]1 year ago

3 0

45-21=24 neutrons :)

As the generally accepted mass of an electron is 0. So, to find the mass of neutrons, minus the protons from the total mass.

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Endpoints of segment MN have coordinates (0, 0), (5, 1). The endpoints of segment AB have coordinates (1 1/22 , 2 1/4 ) and (−2

Nana76 [90]

Answer: $k=18\dfrac{8}{11}$ .

Step-by-step explanation:

If a line passing through two points, then

$Slope=\dfrac{y_2-y_1}{x_2-x_1}$

Endpoints of segment MN have coordinates (0, 0) and (5, 1).

Slope of MN $=\dfrac{1-0}{5-0}=\dfrac{1}{5}$

The endpoints of segment AB have coordinates $\left(1\dfrac{1}{22} , 2\dfrac{1}{4}\right)$ and $\left(-2\dfrac{1}{4} , k\right)$ .

$A=\left(1\dfrac{1}{22} , 2\dfrac{1}{4}\right)=\left(\dfrac{23}{22} ,\dfrac{9}{4}\right)$

$B=\left(-2\dfrac{1}{4} , k\right)=\left(-\dfrac{9}{4} , k\right)$ .

Slope of AB $=\dfrac{k-\frac{9}{4}}{-\frac{9}{4}-\dfrac{23}{22}}$

$=\dfrac{\frac{4k-9}{4}}{\frac{-99-46}{44}}$

$=\dfrac{4k-9}{4}\times \dfrac{44}{-145}$

$=4k-9\times \dfrac{11}{-145}$

$=\dfrac{44k-99}{-145}$

Product of slopes of two perpendicular segments is -1.

Slope of MN × Slope of AB = -1

$\dfrac{1}{5}\times \dfrac{44k-99}{-145}=-1$

$\dfrac{44k-99}{-725}=-1$

$44k-99=725$

$44k=725+99$

$k=\dfrac{824}{44}$

$k=\dfrac{206}{11}$

$k=18\dfrac{8}{11}$

Therefore, the value of k is $k=18\dfrac{8}{11}$ .

8 0

2 years ago

Read 2 more answers

Mai and Tyler work on the equation 2/5b+1=-11 together. Mais soulution is b=-25 and Tyler’s is b=-28. Here is their work. Do you

Anika [276]

Answer:

No I don't agree with their solution; both their answers are wrong.

Correct answer is $b=-30$ .

Step-by-step explanation:

Given:

$\frac{2}{5}b+1=-11$

Now given:

According to Mai $b = -25$ and According to Tyler $b = -28$

Now we need to find which of them is correct.

So we will solve the given equation we get;

$\frac{2}{5}b+1=-11$

Subtracting both side by 1 we get;

$\frac{2}{5}b+1-1=-11-1\\\\\frac{2}{5}b =-12$

Now Multiplying both side $\frac{5}{2}$ we get;

$\frac{2}{5}b\times\frac{5}{2}= -12 \times \frac{5}{2}\\\\b=-6\times 5\\\\b=-30$

Hence both of them are incorrect, correct answer is $b=-30$ .

3 0

2 years ago

Pls help you will get brainliest

cupoosta [38]

Answer:

5/6

Step-by-step explanation:

1/6 + 1/6 = 2/6 TYPE A wood

1/4 + 1/4 = 2/4 TYPE B wood

2/6 + 2/4= ...

2/4 reduces to ?/2

That would be 1/2 because 4 divided by 2 is 2 & 2 divided by 2 is 1.

1/2= ?/6

Its 3/6 because we did 2 x 3 to get 6 and we do the same to the number 1. So we do 1 x 3 = 3

Now we have 3/6 + 2/6!

This is very easy now! We just do 2 + 3 which gets 5.

OUR ANSWER IS 5/6!! Hope this helps! plz mark as brainliest!

8 0

2 years ago

Which segments are parallel?<br> Select each correct answer.<br> O EF<br> O AB<br> O GH<br> O CD

ikadub [295]

Is there an image for the question?

7 0

2 years ago

Read 2 more answers

Which table represents an exponential function?

White raven [17]

Answer:

2nd one is the answer if it's the question

3 0

2 years ago