What are two characteristics of a scientific information source that may indicate the information is unreliable?

Scientific information refers to the classification, collection, dissemination, and retrieval of recorded knowledge treated both as a pure and as an applied science. The two features of a scientific information source, which may suggest that the information is not reliable are:  

1. The information is based on data that are not peer-reviewed, that is, the information has not been reviewed by the experts in the field, or is not encouraged by an accord of experts in the field.  

2. The references are not cited, that is, it not clear or not known that from where the information originated.  

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

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