Is the given system of equations solvable with back substitution?

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Homework Statement



I have attached the question

Homework Equations





The Attempt at a Solution



I think the answer is no solution because there is 5 variables but only 3 equations. Is that correct?
 

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TyErd said:

Homework Statement



I have attached the question

Homework Equations





The Attempt at a Solution



I think the answer is no solution because there is 5 variables but only 3 equations. Is that correct?

No, that is not the reason. Look at the final row; it is shorthand for an equation involving x1, x2, x3, x4, x5. What is the equation?

RGV
 
if the third is also an equation that means there must be an answer right? So because we have to assign variables and we have 5unknowns and 3 equations that must mean two values will be variables right?? so the answer has to be B yeah??
 
TyErd said:
do you mean 0x1 + 0x2 + 0x3 + 0x4 + 0x5 = 4?
For what values of the variables x1, x1, x2, x3, and x4 will this be a true statement?


TyErd said:
if the third is also an equation that means there must be an answer right?
Not necessarily. There are three possibilities for a system of equations (which are here represented by an augmented matrix):
1) a unique solution
2) multiple solutions
3) no solution.
TyErd said:
So because we have to assign variables and we have 5unknowns and 3 equations that must mean two values will be variables right?? so the answer has to be B yeah??