ShmoopTube
Where Monty Python meets your 10th grade teacher.
Search Thousands of Shmoop Videos
Coordinate Geometry Videos 38 videos
In geometry, points are called collinear if they all lie on the same line. What, no bunk beds?
ACT Math 4.1 Coordinate Geometry 238 Views
Share It!
Description:
ACT Math: Coordinate Geometry Drill 4, Problem 1. Find the equation of the line described.
Transcript
- 00:02
For a good time, solve this shmoopy question...
- 00:05
What is the equation of a line perpendicular to Y equals
- 00:09
negative 1/2 X plus four and containing the point 8, 2?
- 00:14
And here are your options...
- 00:16
Okay, so this question is testing whether we know that in
Full Transcript
- 00:20
the land of Y equals MX plus B
- 00:23
were M is the slope of a line. The slope of a line
- 00:26
perpendicular to that line is the negative
- 00:29
inverse of that form. In this example the slope is negative 1/2
- 00:35
so we just need that negative reciprocal so that'll be positive
- 00:39
2 over one or just positive 2. So we can get rid of B and C as potential answers.
- 00:44
We also know that one point this perpendicular line contains is
- 00:49
8 , 2. So all we need to do is plug in these points
- 00:54
into Y equals MX plus B so
- 00:57
we get 2 equals 2 times
- 01:00
8 plus B and we have 2 equals 16 plus B
- 01:04
or B equals -14 and we have Y equals 2x -14
- 01:09
there you go. The answer is E.
Related Videos
ACT Math: Coordinate Geometry Drill 1, Problem 1. Which inequality is expressed by the number line?
ACT Math: Intermediate Algebra: Drill 3, Problem 1. Find the fifth number in the series.
ACT Math: Plane Geometry Drill 3, Problem 1. What is the area of the trapezoid shape in the video?
Haven't you always wondered how much cardboard it takes to encase a trunk warmer for your pet elephant?
Want to figure out the area and perimeter of irregular shapes? Break them down into regular shapes. For example, a flower can be broken down into s...