system

Find the ordered triple (p,q,r) that satisfies the following system:  

p - 2q = 3  

q - 2r = -2 + q  

p + r = 9 + p  

Let's number those equations, for referencing only:  

(1)   p – 2q  =  3   

(2)   q – 2r  =  –2 + q   

(3)   p + r  =  9 + p   

Per equation (2), r = 1   

Per equation (3), r = 9    

You can't have both at the same time.  The system has no solution.  

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