Answer: 42.21 km
Step-by-step explanation:
We can solve this using trigonometry, since we have the following data:
is the the angle of elevation
is the horizontal distance between the plane and the radar station
is the hypotenuse of the right triangle formed between the radar station and the airplane
Now, the trigonometric function that will be used is <u>cosine</u>:
because
is the adjacent side of the right triangle
Finding
:
Answer:
Multiply row 1 by
.
Step-by-step explanation:
The augmented matrix of the system of linear equation is described below:
![\left[\begin{array}{cccc}2&1&-1&-8\\0&2&3&-6\\-\frac{1}{2} &1&1&-4\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D2%261%26-1%26-8%5C%5C0%262%263%26-6%5C%5C-%5Cfrac%7B1%7D%7B2%7D%20%261%261%26-4%5Cend%7Barray%7D%5Cright%5D)
Where
, if we need to create
, we need to multiply row 1 by
, that is to say:
![\left[\begin{array}{cccc}1&\frac{1}{2} &-\frac{1}{2} &-4\\0&2&3&-6\\-\frac{1}{2} &1&1&-4\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D1%26%5Cfrac%7B1%7D%7B2%7D%20%26-%5Cfrac%7B1%7D%7B2%7D%20%26-4%5C%5C0%262%263%26-6%5C%5C-%5Cfrac%7B1%7D%7B2%7D%20%261%261%26-4%5Cend%7Barray%7D%5Cright%5D)
Hence, the correct answer is: Multiply row 1 by
.
Answer:
Reject H0 since test statistic <-2.492
Step-by-step explanation:
Given that the American Water Works Association reports that the per capita water use in a single-family home is 74 gallons per day.
n = 25
x bar = 69
s= 8.3
std error = s/sqrt n = 
H0:
Ha: 
(Left tailed test at 5% significance level)
a) Reject H0 if t
-2.492
b) Test statistic = mean difference/std error
= 
=-3.01
df =24
c) Reject H0