This involves quite a lot of arithmetic to do manually.
The first thing you do is to make the first number in row 2 = to 0.
This is done by R2 = -3/2 R1 + R2
so the matrix becomes
( 2 1 1) ( -3 )
( 0 -13/2 3/2) (1/2 )
(5 -1 2) (-2)
Next step is to make the 5 in row 5 = 0
then the -1 must become zero
You aim for the form
( 1 0 0) (x)
(0 1 0) (y)
(0 0 1) ( z)
x , y and z will be the required solutions.
Answer:

Step-by-step explanation:
Y-intercept:
(8,0) ; x₁ = 8 & y₁ = 0
(3,7) ; x₂= 3 & y₂ = 7
- First find the slope of the line.


slope y-intercept form of the line: y = mx + b
Substitute the slope and x and y in the above equation. We can choose anyone of the given points.

Answer:
$3
Step-by-step explanation:
Let c represent the cost of a box of cereal and let m represent the cost of a jug of milk.
Create a system of equations:
2c + m = 8.5
3c + 2m = 14
Solve by elimination by multiplying the top equation by -2:
-4c - 2m = -17
3c + 2m = 14
Add them together and solve for c:
-c = -3
c = 3
So, a box of cereal costs $3
I’m pretty sure the answer is (2,1)