Answer:
Option C
Step-by-step explanation:
We are given a coefficient matrix along and not the solution matrix
Since solution matrix is not given we cannot check for infinity solutions.
But we can check whether coefficient matrix is 0 or not
If coefficient matrix is zero, the system is inconsistent and hence no solution.
Option A)
|A|=![\left[\begin{array}{ccc}4&2&6\\2&1&3\\-2&3&-4\end{array}\right] =0](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D4%262%266%5C%5C2%261%263%5C%5C-2%263%26-4%5Cend%7Barray%7D%5Cright%5D%20%3D0)
since II row is a multiple of I row
Hence no solution or infinite
OPtion B
|B|=![\left[\begin{array}{ccc}2&0&-2\\-7&1&5\\4&-2&0\end{array}\right] \\=2(10)-2(10)=0](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D2%260%26-2%5C%5C-7%261%265%5C%5C4%26-2%260%5Cend%7Barray%7D%5Cright%5D%20%5C%5C%3D2%2810%29-2%2810%29%3D0)
Hence no solution or infinite
Option C
![\left[\begin{array}{ccc}6&0&-2\\-2&0&6\\1&-2&0\end{array}\right] \\=2(36-2)=68](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D6%260%26-2%5C%5C-2%260%266%5C%5C1%26-2%260%5Cend%7Barray%7D%5Cright%5D%20%5C%5C%3D2%2836-2%29%3D68)
Hence there will be a unique solution
Option D
![\left[\begin{array}{ccc}5&10&5\\4&1&4\\-1&-2&-1\end{array}\right] \\=2(10)-2(10)=0](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D5%2610%265%5C%5C4%261%264%5C%5C-1%26-2%26-1%5Cend%7Barray%7D%5Cright%5D%20%5C%5C%3D2%2810%29-2%2810%29%3D0)
=0
(since I row is -5 times III row)
Hence there will be no or infinite solution
Option C is the correct answer
<h3>
Answer: C) 70 degrees</h3>
=========================================================
Explanation:
We have n = 6 sides, so the interior angles must add to 180(n-2) = 180(6-2) = 720 degrees
Lets add up the angles, set the sum equal to 720 and solve for x
x+2x+115+2x+115+2x = 720
7x+230 = 720
7x = 720-230
7x = 490
x = 490/7
x = 70
This makes angle 2x = 2*70 = 140 degrees
We see that x = 70 is the smallest angle, so that's why C is the answer.
Answer:
x = 
y = 
Step-by-step explanation:
![2x-3y=5\\5x=4y=14\\\\\left[\begin{array}{cc}2&-3\\5&-4\\\end{array}\right] \left[\begin{array}{c}x\\y\\\end{array}\right] =\left[\begin{array}{c}5\\14\\\end{array}\right]](https://tex.z-dn.net/?f=2x-3y%3D5%5C%5C5x%3D4y%3D14%5C%5C%5C%5C%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D2%26-3%5C%5C5%26-4%5C%5C%5Cend%7Barray%7D%5Cright%5D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7Dx%5C%5Cy%5C%5C%5Cend%7Barray%7D%5Cright%5D%20%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7D5%5C%5C14%5C%5C%5Cend%7Barray%7D%5Cright%5D)
Let A = ![\\\left[\begin{array}{cc}2&-3\\5&-4\\\end{array}\right]](https://tex.z-dn.net/?f=%5C%5C%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D2%26-3%5C%5C5%26-4%5C%5C%5Cend%7Barray%7D%5Cright%5D)
The inverse of A multiplied by A = the identity matrix ![\left[\begin{array}{cc}1&0\\0&1\\\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D1%260%5C%5C0%261%5C%5C%5Cend%7Barray%7D%5Cright%5D)
Inverse of A = 
![\left[\begin{array}{ccc}-4&3\\-5&2\\\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-4%263%5C%5C-5%262%5C%5C%5Cend%7Barray%7D%5Cright%5D)
detA = ad - bc = 
Inverse of A = ![\left[\begin{array}{cc}\frac{-4}{7} &\frac{3}{7} \\\frac{-5}{7} &\frac{2}{7}\\\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D%5Cfrac%7B-4%7D%7B7%7D%20%26%5Cfrac%7B3%7D%7B7%7D%20%5C%5C%5Cfrac%7B-5%7D%7B7%7D%20%26%5Cfrac%7B2%7D%7B7%7D%5C%5C%5Cend%7Barray%7D%5Cright%5D)
![\left[\begin{array}{ccc}x\\y\\\end{array}\right] = \left[\begin{array}{cc}\frac{-4}{7} &\frac{3}{7} \\\frac{-5}{7} &\frac{2}{7}\\\end{array}\right] \left[\begin{array}{ccc}5\\14\\\end{array}\right] = \left[\begin{array}{ccc}\frac{22}{7} \\\frac{3}{7} \\\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Dx%5C%5Cy%5C%5C%5Cend%7Barray%7D%5Cright%5D%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D%5Cfrac%7B-4%7D%7B7%7D%20%26%5Cfrac%7B3%7D%7B7%7D%20%5C%5C%5Cfrac%7B-5%7D%7B7%7D%20%26%5Cfrac%7B2%7D%7B7%7D%5C%5C%5Cend%7Barray%7D%5Cright%5D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D5%5C%5C14%5C%5C%5Cend%7Barray%7D%5Cright%5D%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D%5Cfrac%7B22%7D%7B7%7D%20%5C%5C%5Cfrac%7B3%7D%7B7%7D%20%5C%5C%5Cend%7Barray%7D%5Cright%5D)
Answer:
$15
Step-by-step explanation:
if one pound is $5 and we need 3, then we can multiply the price of one pound by 3. (3×$5) This gives $15
Answer:
A Sasha, because the points are of different signs
