An indirect proof starts with the assumption that the statement we are trying to prove is not true.
The two lines are not parallel.
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An indirect proof starts with the assumption that the statement we are trying to prove is not true.
In this case, the conclusion of the conditional statement is that two lines are parallel.
The negation of this statement is that the two lines are not parallel.
The two lines areparallel.
⇓
The two lines are notparallel.
Finally, we can state the assumption we would make to start the indirect proof.
Assumption:
The two lines are not parallel.
