Step-by-step explanation:
By Pythagoras' theorem,
12^2 = 11^2 + height^2
height = ±√12^2 - 11^2 (rej -ve value since height > 0)
height = 16.279 (5sf) = 16.3 (nearest tenth place)
Topic: Pythagoras theorem
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Answer:
Hence, the total cost of mailing 10 ounces is:
$ 2.52
Step-by-step explanation:
If postage costs $.54 for the first ounce and $.22 for the each additional ounce.
i.e. cost of first ounce=$ 0.54.
Now let x denote the number of ounces after the first ounce,
Hence, the cost of x ounces=$ (0.22×x)=$ 0.22 x
Hence, the cost of mailing (x+1) ounces is: $ (0.54+0.22 x)
Now, we have to find the cost of mailing a 10- ounce envelope.
i.e. after the first ounce we need 9 more ounces.
Hence, the total cost of mailing is calculated as:

Hence, cost of mailing 10 ounces is:
$ 2.52
Answer:
The standard error of the mean is 0.0783.
Step-by-step explanation:
The Central Limit Theorem helps us find the standard error of the mean:
The Central Limit Theorem estabilishes that, for a random variable X, with mean
and standard deviation
, a large sample size can be approximated to a normal distribution with mean
and standard deviation
.
The standard deviation of the sample is the same as the standard error of the mean. So

In this problem, we have that:

So



The standard error of the mean is 0.0783.
Answer:
Option 1: CD is a perpendicular bisector of AB
Step-by-step explanation:
Let us find out the slopes of various line segments and the Distances and then we will draw the conclusions accordingly.
Formula to find slope

Formula to Find Distance between two points

mAB ( represents , Slope of AB )
1. 
2. 
3. 
4. 
5. 
mAC = mBC , and C is common point , hence these three are collinear points making a straight line whole slope is 



Hence CD ⊥ AB
Also
From Point 4 and point 5 above , we see that
AC = CB
Hence CD bisect AB at C, also CD ⊥ AB
There fore
CD is a perpendicular bisector of AB
Therefor option 1 is true
I am going to explain this using the substitution method, considering it appears to be the best in this situation.
We know (from the bottom equation) that y can equal 3x+20. Using this knowledge, we substitute the y in the top equation for 3x+20. Now, we have an equation that looks like this:
3x+20=x^2+2x
Now we need to move x to one side and then do some radicals (square roots).
Subtract the 2x on the right (since it is smaller, negatives = NONONO), which will give you
x+20=x^2
Now, we take the square root of both sides to get
rad(x+20)=x
Now we have to simplify. 20 doesn't have a square root, but 4 goes into 20, and 4 has a square root of 2. This now becomes
2rad(x+5)
This doesn't simplify any further... we have a problem... no way to isolate x as far as my knowledge goes... Sorry, can't help you any further than that, but another person or your teacher might be able to. R.I.P...