Sorry i cant see the picture so well
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:
correct answer is x = 2.75
Step-by-step explanation:
Given;
AB = 2x-5
BC = 6x
AC = 27
Hence,
=> AC = AB + BC
=> 27 = 2x-5 + 6x
=> 27 = 8x-5
=> 27-5 = 8x
=> 22 = 8x
=> 22/8 = x
=> 11/4 = x
or
2.75 = x
