What is the length of the line?

mr Goodwill [35]

Start the equation by putting the equations equal to each other 3x+14=7x-10
Next +10 on both sides
3x+14=7x-10
+10 +10
You are left with 3x+24=7x
because the 10's canceled each other out.
Next -3x on both sides
3x+24=7x
-3x +3x

You are left with 24= 10x
because like before the 3's canceled each other out
Now you will divide both sides by 10

24=10x
---- -----
10 10

2.4= X is the answer!

8 0

3 years ago

Can someone please. Help, thanks

erastovalidia [21]

Answer:

Do you mean like on the line it would be x=3 or where you looking for a different type of answer?sorry if this isn't too helpful

Step-by-step explanation:

7 0

3 years ago

Read 2 more answers

Please I need the answer quickly

USPshnik [31]

Well, for number 15, this is what I came up with, I hope it is what your teacher is looking for:
So it starts out with 3 butterflies, and it doubles every minute:
3x2 = 6 That is for the first minute
6x2 = 12 That is for the second minute
12x2 = 24 That is for the third minute
24x2 = 48 That is for the fourth minute

So, It asks for using the power of 2 in your answer, that is what I came up with for part A.

For part B I would say something like this:

X represents the number of butterflies left.
The equation, using the information above would be this:

48-7 = X
Then simplify, which would leave you with 41 butterflies.

I hope this helps! :)

4 0

3 years ago

Find the perimeter of a train of 100 equilateral triangles if the triangles are joined side to side. Each side is one inch long.

yarga [219]

Answer:

102

Step-by-step explanation:

Each triangle will have a perimeter of 3. When joined, the outside triangles will have 2 sides showing, or 2 inches. The middle 98 will only have one free side, or one inch. This means that 98*1 + 2*2 = 102

7 0

3 years ago

An certain brand of upright freezer is available in three different rated capacities: 16 ft3, 18 ft3, and 20 ft3. Let X = the ra

ruslelena [56]

Answer:

$E(X)=16\cdot 0.3+18\cdot 0.1+20\cdot 0.6=18.6$

$E(X^2)=16^2\cdot 0.3+18^2\cdot 0.1+20^2\cdot 0.6=349.2$

$V(X) = E(X^2)-[E(X)]^2=349.2-(18.6)^2=3.24$

The expected price paid by the next customer to buy a freezer is $466

Step-by-step explanation:

From the information given we know the probability mass function (pmf) of random variable X.

$\left|\begin{array}{c|ccc}x&16&18&20\\p(x)&0.3&0.1&0.6\end{array}\right|$

Point a:

The Expected value or the mean value of X with set of possible values D, denoted by E(X) or μ is

$E(X) = $\sum_{x\in D} x\cdot p(x)$

Therefore

$E(X)=16\cdot 0.3+18\cdot 0.1+20\cdot 0.6=18.6$

If the random variable X has a set of possible values D and a probability mass function, then the expected value of any function h(X), denoted by E[h(X)] is computed by

$E[h(X)] = $\sum_{D} h(x)\cdot p(x)$

So $h(X) = X^2$ and

$E[h(X)] = $\sum_{D} h(x)\cdot p(x)\\E[X^2]=$\sum_{D}x^2\cdot p(x)\\ E(X^2)=16^2\cdot 0.3+18^2\cdot 0.1+20^2\cdot 0.6\\E(X^2)=349.2$

The variance of X, denoted by V(X), is

$V(X) = $\sum_{D}E[(X-\mu)^2]=E(X^2)-[E(X)]^2$

Therefore

$V(X) = E(X^2)-[E(X)]^2\\V(X)=349.2-(18.6)^2\\V(X)=3.24$

Point b:

We know that the price of a freezer having capacity X is 60X − 650, to find the expected price paid by the next customer to buy a freezer you need to:

From the rules of expected value this proposition is true:

$E(aX+b)=a\cdot E(x)+b$

We have a = 60, b = -650, and E(X) = 18.6. Therefore

The expected price paid by the next customer is

$60\cdot E(X)-650=60\cdot 18.6-650=466$

4 0

3 years ago