I'll solve 21, and you then should be able to solve the rest on your own!
Since ADC is 135, that means that that whole angle is 135 degrees. In addition, since angles ADB and BDC add up to ADC, we get ADB+BDC=ADC=135=11x+9+7x=18x+9. Subtracting 9 from both sides, we get 126=18x. Dividing both sides by 18, we get x=7. Plugging that into 11x+9=BDC, we get 11*7+9=77+9=86
Answer:
a) 
b) The should sample at least 293 small claims.
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
.
So it is z with a pvalue of
, so
, which means that the answer of question a is 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.
(b) If the group wants their estimate to have a maximum error of $12, how many small claims should they sample?
They should sample at least n small claims, in which n is found when
. So







The should sample at least 293 small claims.
x - √3y - 4 = 0 → <u>Choice</u><u> </u><u>A</u>
Step-by-step explanation:
x - 4 = √3y
x - 4 <u>- √3y</u> = √3y <u>- √3y</u>
x - 4 - √3y = 0
x - √3y - 4 = 0
The answer is i don’t know or I don’t care and what are we trying to find
Answer:
-4
Step-by-step explanation:
[√2(cos(3π/4) + i sin(3π/4))]⁴
(√2)⁴ (cos(3π/4) + i sin(3π/4))⁴
4 (cos(3π/4) + i sin(3π/4))⁴
Using De Moivre's Theorem:
4 (cos(4 × 3π/4) + i sin(4 × 3π/4))
4 (cos(3π) + i sin(3π))
3π on the unit circle is the same as π:
4 (cos(π) + i sin(π))
4 (-1 + i (0))
-4