Answer: The 95% confidence interval is approximately (55.57, 58.43)
======================================================
Explanation:
At 95% confidence, the z critical value is about z = 1.960 which you find using a table or a calculator.
The sample size is n = 17
The sample mean is xbar = 57
The population standard deviation is sigma = 3
The lower bound of the confidence interval is
L = xbar - z*sigma/sqrt(n)
L = 57 - 1.960*3/sqrt(17)
L = 55.5738905247863
L = 55.57
The upper bound is
U = xbar + z*sigma/sqrt(n)
U = 57 + 1.960*3/sqrt(17)
U = 58.4261094752137
U = 58.43
Therefore the confidence interval (L, U) turns into (55.57, 58.43) which is approximate.
Answer: sin
= ± 
Step-by-step explanation:
We very well know that,
cos2A=1−2sin²A
⟹ sinA = ±
As required, set A = & cos a= 
,thus we get
sin =± 
∴ sin =±
= ±
since ,360° < <450°
,180° < <225°
Now, we are to select the value with the correct sign. It's is obvious from the above constraints that the angle a/2 lies in the III-quadrant where 'sine' has negative value, thus the required value is negative.
hope it helped!
Your question is very confusing but x=8 so just plug in 8 where you see X
Y - y1 = m(x - x1)
slope(m) = -4/3
(0,-12)....x1 = 0 and y1 = -12
sub
y - (-12) = -4/3(x - 0) =
y + 12 = -4/3(x - 0) <=== point slope form
y + 12 = -4/3x
y = -4/3x - 12 <=== slope intercept form
y = -4/3x - 12
4/3x + y = -12
4x + 3y = -36 <=== standard form
