Parallel Lines
Parallel Lines- coplanar lines that never intersect
Parallel Lines in the Real World
Parallel lines are found everywhere in life. Just look around, since your eyes are obviously glued to the computer screen, we'll start there. The top and bottom edges of the screen are parallel, as are the left and right edges. Also, the line formed where the ceiling and wall meet is parallel to the one formed by the wall and the floor. Thinking a bit larger, the columns of the coliseum are parallel to each other.
Parallel Theorems
IF two lines are cut by a transversal so that...
-alternate exterior angles are congruent
-alternate interior angles are congruent
- corresponding angles are congruent>
- two interior angles on the same side of tthe transversal
are supplementary
-two exterior angles on the same side of thhe transversal
are supplementary
-two coplanar lines are perpendicular to a third line
... the lines are parallel
Sample Problem