Parallel Lines Parallel lines are two lines in the same plane
with the same slope. They never cross even if both lines were
extended infinitely in both directions Look back at our examples:
What would happen if the railroad tracks ever crossed? What about
if the yard lines on a football field werent the same distance
apart at any point? Why would the even bars in gymnastics need to
be parallel?
Slide 4
Perpendicular Lines In Everyday Life
Slide 5
Perpendicular Lines Perpendicular lines are two lines that
intersect to form a right angle. They only intersect at one point
Look back at our examples: Why is plaid perpendicular? Why are
window panes perpendicular? Why may an intersection need to be a 90
degree angle?
Slide 6
Skew Lines Lines in the same plane that do not intersect and
are not parallel. Think of ideas in which you could find this to be
possible. What about if you were given a cube?
Slide 7
Skew Lines Notice that the two green lines will never intersect
yet they are not parallel
Slide 8
Parallel Planes Lets consider the cube example again
Slide 9
Perpendicular Planes Lets consider the cube example again
Slide 10
Perpendicular Planes Consider if you had two pieces of paper
and cut a slice in one. If they intersected their intersection
would be a line.