Algebra

 

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

p - 2q = 3    

q - 2r = -2 + q    

p + r = 9 + p    

 

Look at the system    

 

q – 2r  =  –2 + q     ==>>     –2r = –2     ==>>    r = 1    

 

p + r  =  9 + p         ==>>                                   r = 9    

 

r can't be both 1 and 9, therefore the system is not valid and there is no solution.    

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