Indirect Proof: all possibilities are considered then all but one are proved false.
First Step: Assume that the opposite of what you are to prove is true.
Second Step: Prove it is false by using definitons, theorems, or postualtes.
Third Step: State the assumption is false and what you wanted to prove is true.
What is an Indirect Proof?
all possibilities are considered then all but one are proved false. a>