Show the relation is an implicit solution of the DiffEQ

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Homework Statement



Differential equation: 2xyy' = x^2 + y^2
Relation: y^2 = x^2 - cx

Homework Equations





The Attempt at a Solution


Hello, I can normally solve this problems with ease; however, I am having trouble with this particular problem. I have performed the implicit differentiation to get: (2yy' = 2x - c). However, I can't seem to figure out where to go from here. I am thinking that perhaps there is some obvious simplification that I am missing. If somebody can point me in the right direction I'd greatly appreciate it. Thanks.
 
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Multiply 2yy' = 2x-c by x so that the lefthand sides look the same and use 2x^2 = x^2+x^2.
 
thank you very much, I figured I was missing something somewhat obvious
 
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