ShmoopTube

Where Monty Python meets your 10th grade teacher.

Search Thousands of Shmoop Videos


Coordinate Geometry Videos 38 videos

Midsegment Theorem
4647 Views

Who knew triangles had midsegments? We did.

Collinearity
369 Views

In geometry, points are called collinear if they all lie on the same line. What, no bunk beds?

Finding the Distance Between Two Points
2065 Views

Talk about math being applicable to real life.

See All

ACT Math 5.4 Coordinate Geometry 385 Views


Share It!


Description:

ACT Math: Coordinate Geometry Drill 5, Problem 4. Find the other endpoint.

Language:
English Language

Transcript

00:02

Here's another shmoop du jour...

00:05

One endpoint of a line segment is (3, -4). If the midpoint is (2, 1), what is the other

00:12

endpoint? And here are your potential answers...

00:17

Ok so this question is asking us to basically apply the midpoint formula...

00:20

Okay... if we're given two points....x1, y1, and x2, y2...

00:24

...the midpoint between the two points can be found with the formula: x1 plus x2 divided

00:30

by 2, y1 plus y2 divided by 2. But we're not given the two endpoints. Instead,

00:37

we're given the midpoint and one other point...

00:40

Not a problem. Let's place these values in the midpoint formula.

00:44

(2,1) equals the quantity 3 plus x... divided by 2... and the quantity negative 4 plus y

00:50

divided by 2. So the x coordinate equation is 2 equals 3

00:56

plus x divided by 2...and the y coordinate is 1 equals negative 4 plus y divided by 2.

01:03

Now let's go to the x coordinate equation. Multiply both sides by 2...

01:07

So 4 equals 3 plus x. Then we subtract both sides by 3..

01:12

So the x coordinate is 1.

01:14

Well, now let's go to the y-coordinate equation.

01:17

Multiply both sides by 2. 2 equals negative 4 plus y. Add 4 to both sides...

01:22

So y equals 6. And yeah, it's answer choice E!

Related Videos

ACT Math 3.1 Plane Geometry
2559 Views

ACT Math: Plane Geometry Drill 3, Problem 1. What is the area of the trapezoid shape in the video?

Inequalities in Number Lines
3229 Views

ACT Math: Coordinate Geometry Drill 1, Problem 1. Which inequality is expressed by the number line?

ACT Math 3.1 Intermediate Algebra
1955 Views

ACT Math: Intermediate Algebra: Drill 3, Problem 1. Find the fifth number in the series.

Parallel Lines and Transversals
34135 Views

This video explores parallel lines and transversals: how to identify them both on a math test and in real life urban planning. What do the consecut...

Proving Lines are Perpendicular
795 Views

Prove it, Shmoopers. We dare you.