Answer: 12.5
Step-by-step explanation:
you go on the web and google area of trapezium
You can buy 5 bottles because $4 times 5 equals $20. I hope this helps :)
8c -c= 7c
7c+6=48
7c=42
c=6
CHECK:
8(6)-(6)+6=48
48-6=42
42+6=48
48=48
Answer: The system of equations is:
x + 2y + 2 = 4
y - 3z = 9
z = - 2
The solution is: x = -22; y = 15; z = -2;
Step-by-step explanation: ONe way of solving a system of equations is using the Gauss-Jordan Elimination.
The method consists in transforming the system into an augmented matrix, which is writing the system in form of a matrix and then into a <u>Row</u> <u>Echelon</u> <u>Form,</u> which satisfies the following conditions:
- There is a row of all zeros at the bottom of the matrix;
- The first non-zero element of any row is 1, which called leading role;
- The leading row of the first row is to the right of the leading role of the previous row;
For this question, the matrix is a Row Echelon Form and is written as:
![\left[\begin{array}{ccc}1&2&2\\0&1&3\\0&0&1\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D1%262%262%5C%5C0%261%263%5C%5C0%260%261%5Cend%7Barray%7D%5Cright%5D)
![\left[\begin{array}{ccc}4\\9\\-2\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D4%5C%5C9%5C%5C-2%5Cend%7Barray%7D%5Cright%5D)
or in system form:
x + 2y + 2z = 4
y + 3z = 9
z = -2
Now, to determine the variables:
z = -2
y + 3(-2) = 9
y = 15
x + 30 - 4 = 4
x = - 22
The solution is (-22,15,-2).
The general formula for the margin of error would be:
z * √[p (1-p) ÷ n]
where:
z = values for selected confidence level
p = sample proportion
n = sample size
Since the confidence level is not given, we can only solve for the
<span>√[p (1-p) ÷ n] part.
</span>
p = 44/70
n = 70
√[44/70 (1 - (44/70) ÷ 70]
√[0.6286 (0.3714)] ÷ 70
√0.2335 ÷ 70
√0.0033357 = 0.05775 or 0.058 Choice B.