Answers:
B = 50
a = 10.9
c = 17.0
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Explanation:
This is a right triangle, so the acute angles are complementary, meaning they add to 90
B+40 = 90
B+40-40 = 90-40
B = 50
Also, because this is a right triangle, we can use trig ratios to compute the missing sides
tan(angle) = opposite/adjacent
tan(40) = a/13
a = 13*tan(40)
a = 10.908
a = 10.9
cos(angle) = adjacent/hypotenuse
cos(40) = 13/c
c*cos(40) = 13
c = 13/cos(40)
c = 17.0
note: make sure your calculator is in degree mode
Answer:
A 90% confidence interval for the mean number of letter sounds identified in one minute is: (30.84, 37.34).
Step-by-step explanation:
We have that to find our
level, that is the subtraction of 1 by the confidence interval divided by 2. So:

Now, we have to find z in the Ztable as such z has a pvalue of
.
That is z with a pvalue of
, so Z = 1.645.
Now, find the margin of error M as such

In which
is the standard deviation of the population and n is the size of the sample.


The lower end of the interval is the sample mean subtracted by M. So it is 34.09 - 3.25 = 30.84.
The upper end of the interval is the sample mean added to M. So it is 34.09 + 3.25 = 37.34.
A 90% confidence interval for the mean number of letter sounds identified in one minute is: (30.84, 37.34).
Answer:
cos(B) = a/c
Step-by-step explanation:
The mnemonic SOH CAH TOA reminds you that ...
Cos = Adjacent/Hypotenuse
The leg adjacent to angle B is "a". The hypotenuse is "c", so the desired cosine is ...
cos(B) = adjacent/hypotenuse = a/c
Answer:
f(-2)=4(-2)+1= 7
Step-by-step explanation: