Complementary and Supplementary Angles

Not to be confused with complimentary angles, which are just the nicest angles you'll ever meet.

Basic GeometryAngles
GeometryAngles
LanguageEnglish Language

Transcript

00:25

if they allowed him to build it...Plus that way he won't depress the rest of [little girl crying]

00:29

the visitors while building one of the windows for the funhouse

00:33

Claude finds that the window needs a diagonal brace to support it if the

00:38

corner of the window is at a right angle and the brace is at a 50 degree angle

00:43

from the bottom how many degrees from the side is the brace? all right so let's [Girl sitting at a table with a coffee]

00:49

think this through first things first let's label our angles the corner of the

00:54

window is a right angle so let's indicate that with a box in the corner

00:58

it's also good to keep in mind that right angles are 90 degrees in measure

01:03

the only other angle we know is from the bottom to the brace which is 50 degrees

01:08

we want to find the measure of the other angle since we don't know it yet let's

01:13

call it X to solve this we can use the idea of complementary angles or two [Two angles complementing each other]

01:23

angles whose measures add up to 90 degrees since X and the 50 degree angle

01:28

add up to 90 degrees we can find X by solving the equation X plus 50 equals 90

01:35

subtracting 50 from both sides gives us a value of 40 degrees for X feeling a

01:40

little less sad Claude goes on to build the floor he wants to make the door to [Claude appears with a hammer]

01:44

the funhouse tilted so that it's at an angle of 65 degrees

01:49

how tilted must the doorframe be in relation to the wall? Again we should

01:54

start by labeling our angles we know that the angle of the door is 65 degrees

01:59

and we'll call the other one X since we don't know it yet even though the door

02:03

frame is tilted the floor is still a straight angle since we know straight [Tilted door appears]

02:07

angles are 180 degrees in measure the two angles here are supplementary

02:12

angles or two angles whose measures add up to 180 degrees... since we know that two

02:19

angles add up to 180 degrees we can set the equation X plus 65 equals 180 and

02:26

solve for X so subtracting 65 from both sides gives us x equals 115 degrees as [65 subtracted from both angles]

02:33

our answer Claude has figured out all the angles in

02:37

his funhouse and building it has made him much happier he still has the

02:41

occasional relapse but he's cut down his sobbing sessions to only about once [Claude sobbing and the Joker appears]

02:45

a week