Answer:
C. {-9,-3}
Step-by-step explanation:
gives 
if 
. This gives 
, which is valid.
It can also give 
if 
. This gives 
, which is valid.
Hence the solutions are 
.
Your answer is C. Think of the x axis as the ground.
The correct answer is: [B]: " y = 9 " .
_____________________________________________
A. The point estimate of μ1 − μ2 is calculated using the value of x1 - x2, therefore:
μ1 − μ2 = x1 – x2 =
7.82 – 5.99
μ1 − μ2 = 1.83
B. The formula for
confidence interval is given as:
Confidence interval
= (x1 –x2) ± z σ
where z is a value
taken from the standard distribution tables at 99% confidence interval, z =
2.58
and σ is calculated
using the formula:
σ = sqrt [(σ1^2 /
n1) + (σ2^2 / n2)]
σ = sqrt [(2.35^2 /
18) + (3.17^2 / 15)]
σ = 0.988297
Going back to the
confidence interval:
Confidence interval
= 1.83 ± (2.58) (0.988297)
Confidence interval
= 1.83 ± 2.55
Confidence interval
= -0.72, 4.38
Answer:
22.5 miles per hour
Step-by-step explanation:
<u>Given system of equations</u>
5(s-w)=900
4(s+w)=900
<u />
<u>Set equations equal to each other</u>
5(s-w)=4(s+w)
5s-5w=4s+4w
s-5w=4w
s=9w
<u>Solve for w using the substitution s=9w</u>
4(s+w)=900
4(9w+w)=900
4(10w)=900
40w=900
w=22.5
Therefore, the speed of the wind is 22.5 miles per hour
