Answer:
A
Step-by-step explanation:
The answer to your question is $1978
First distribute in the 2 on the left side to get 6d+6=7+6d
Then, you would combine the variables to be on one side of the equation by doing -6d. However, this would cancel out the d by leaving you with 0d+6=7. That is the same thing as saying 6=7.
The answer to this equation is no solution because 6 is NOT equal to 7.
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.
