Question 976765: For the following systems of equations in echelon form, tell how many solutions there are in nonnegative integers. x - 7y+4z = 75; 2y+7z=60.
Thanks a bunch!
Answer by MathLover1(20849) (Show Source):
You can put this solution on YOUR website! our matrix
Find the pivot in the 1st column in the 1st row
Make the pivot in the 2nd column by dividing the 2nd row by 2
Eliminate the 2nd column
Solution set:


- free
Therefore the solutions can be written as
( , , ) = ( , , )
Because we want to find non-negative solutions, we have three inequalities


so,



and
so, the integer values of satisfying all of those inequalities , , and are
= , , , , , , , ,
so, there will be nine non-negative solutions
|
|
|