ShmoopTube
Where Monty Python meets your 10th grade teacher.
Search Thousands of Shmoop Videos
Plane figures (triangles, rectangles, parallelograms, trapezoids, circles, polygons) Videos 10 videos
ACT Math: Plane Geometry Drill 3, Problem 5. How long would it take for the wheel to make two rotations?
One formula to rule them all, one formula to find them. One formula to bring them all, and in the darkness bind them. Or something like that. I...
All You Need to Know about Slopes of Parallel and Perpendicular Lines 2756 Views
Share It!
Description:
So many parallel and perpendicular lines all over the place, and none of them have been labeled. Which begs the question: whose lines are they, anyway?
Transcript
- 00:04
Slopes of parallel and perpendicular lines, a la Shmoop. [title page]
- 00:08
Two magician's apprentices have turned their master into a bear--which is a problem, because [magician turns into bear]
- 00:13
he's an angry bear. [bear chases kids]
- 00:15
Help them figure out what went wrong by calculating whether the slopes of their magic rays were
- 00:20
parallel or perpendicular.
Full Transcript
- 00:22
The equations of their magic rays are: y=3x+4 and y=3x+10. [equations shown]
- 00:30
Fortunately, these equations are already set up in slope-intercept form (y=mx+b, where [equations on slopes]
- 00:38
m is the slope). [slope-intercept form demonstrated]
- 00:41
That means that the slope in each equation is 3.
- 00:45
According to the Magician's Apprentice Handbook, "If two lines are perpendicular, their slopes [handbook opens]
- 00:50
are negative reciprocals of each other."
- 00:53
Negative reciprocals, when multiplied together, equal -1. [negative reciprocals defined]
- 00:58
3 x -1/3 = -1, so if one of the two equations had a slope of -1/3, then these two equations
- 01:08
would be perpendicular to each other. [perpendicular lines explained]
- 01:10
If two lines are parallel, their slopes are the same. [parallel lines defined]
- 01:14
Since we know each equation has a slope of 3, their slopes are parallel.
- 01:19
Oh, here it is, page 32... [handbook opens]
- 01:22
"Parallel magic rays deployed at the same time result in... bear."
- 01:27
Magical antidote?
- 01:28
Get rid of the evidence. [kids run from bear]
Related Videos
We don't like knocking people down to size, but we do like simplifying radicals. Join us?
If fleeing criminals always fled the scene of the crime at perfect right angles, it would be much easier to determine their whereabouts. Fortunatel...
Okay, so this probably isn't going to help you master Pokemon Go, but game theory can be applied to all sorts of situations. Even stomping your old...
Today's video is about calculating central tendency. We'll lay out outliers and make means...meaningful.