Answer:

Step-by-step explanation:
To find the matrix A, took all the numeric coefficient of the variables, the first column is for x, the second column for y, the third column for z and the last column for w:
![A=\left[\begin{array}{cccc}1&1&2&2\\-7&-3&5&-8\\4&1&1&1\\3&7&-1&1\end{array}\right]](https://tex.z-dn.net/?f=A%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D1%261%262%262%5C%5C-7%26-3%265%26-8%5C%5C4%261%261%261%5C%5C3%267%26-1%261%5Cend%7Barray%7D%5Cright%5D)
And the vector B is formed with the solution of each equation of the system:![b=\left[\begin{array}{c}3\\-3\\6\\1\end{array}\right]](https://tex.z-dn.net/?f=b%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7D3%5C%5C-3%5C%5C6%5C%5C1%5Cend%7Barray%7D%5Cright%5D)
To apply the Cramer's rule, take the matrix A and replace the column assigned to the variable that you need to solve with the vector b, in this case, that would be the second column. This new matrix is going to be called
.
![A_{2}=\left[\begin{array}{cccc}1&3&2&2\\-7&-3&5&-8\\4&6&1&1\\3&1&-1&1\end{array}\right]](https://tex.z-dn.net/?f=A_%7B2%7D%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D1%263%262%262%5C%5C-7%26-3%265%26-8%5C%5C4%266%261%261%5C%5C3%261%26-1%261%5Cend%7Barray%7D%5Cright%5D)
The value of y using Cramer's rule is:

Find the value of the determinant of each matrix, and divide:


The answer is C
i think so
Answer:
There are 5,586,853,480 different ways to select the jury.
Step-by-step explanation:
The order is not important.
For example, if we had sets of 2 elements
Tremaine and Tre'davious would be the same set as Tre'davious and Tremaine. So we use the combinations formula.
Combinations formula:
is the number of different combinations of x objects from a set of n elements, given by the following formula.

In how many different ways can a jury of 12 people be randomly selected from a group of 40 people?
Here we have
.
So

There are 5,586,853,480 different ways to select the jury.
Answer:
B. 1 in = 7 ft
Step-by-step explanation:
Since on the scale the boat was 6 inches and the actual boat was 42 feet, we need to divide to see how many feet correlate to the number on inches on the scale. So we do 42 / 6, which equals 7. This means that for every inch on the scale, it will be 7 feet in real life.