ClassX Video Lessons Youtube Channel Smile and Learn English ANGLE Subtraction ➖ Sexagesimal System ???? Math for Kids
Hello friends! Today, we’re going to learn how to subtract angles. Are you ready to dive in?
We use something called the sexagesimal system to measure angles. This means angles are measured in degrees, minutes, and seconds. Here’s a quick reminder:
Let’s learn how to subtract angles with an example. It’s easier than you might think!
First, we need to arrange the angles we want to subtract. Place the smaller angle under the bigger angle, just like in regular subtraction. To find out which angle is bigger, we compare the degrees first. If the degrees are the same, we compare the minutes, and if those are the same too, we look at the seconds.
For example, let’s subtract 128° 9′ 57″ from 245° 12′ 25″. The first angle is bigger because it has more degrees, so it goes on top.
We start by subtracting the seconds. If we need to subtract 57 seconds from 25 seconds, we can’t do it directly. So, we borrow 1 minute from the minutes column, which gives us 60 extra seconds. Now, we have 11 minutes and 85 seconds (because 60 + 25 = 85).
Next, we subtract the minutes. If the top number is smaller than the bottom, we borrow 1 degree from the degrees column, which gives us 60 extra minutes. Then, we continue with the subtraction.
Finally, we subtract the degrees. Let’s see how it all works out:
So, the final result is 117° 2′ 28″. Great job! Wasn’t that simpler than it looked?
Now it’s your turn to practice! The more you practice, the better you’ll get at subtracting angles.
We’ve learned a lot today, and there’s so much more to discover. Keep exploring and learning, and you’ll be amazed at how much you can achieve!
Gather your classmates and form teams. Each team will be given a set of angle subtraction problems. Race against the clock to solve them correctly. The first team to finish with all correct answers wins! This will help you practice subtracting angles quickly and accurately.
Use your creativity to make up your own angle subtraction problems. Write them down and swap with a partner to solve each other’s problems. This activity will help you understand the process better and see how others approach the same task.
Use an online math game platform to play angle subtraction games. These games are designed to make learning fun and interactive. You’ll get instant feedback on your answers, helping you learn from any mistakes.
Create a storyboard that illustrates the steps of subtracting angles. Use drawings or digital tools to show each step visually. This will help you remember the process and make it easier to explain to others.
Organize a quiz show in class where you and your classmates answer angle subtraction questions. Take turns being the quizmaster and contestant. This will reinforce your knowledge and make learning competitive and exciting.
Here’s a sanitized version of the provided YouTube transcript:
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[Music]
Hello friends! In the previous lesson, we learned how to add angles, and today we’re going to learn how to subtract them. Are you ready?
As you know, we use the sexagesimal system to measure angles, which means they are measured in degrees, minutes, and seconds. Remember that 1° equals 60 minutes and 1 minute equals 60 seconds.
Today, we’ll learn how to subtract angles with some examples, and you’ll see how easy it is!
The first step is to place the angle measures we want to subtract in the same format as normal subtraction: the smaller angle under the bigger angle. How do we know which one is bigger? We look at the degrees. The angle with the largest degree will be the larger angle. If the degrees are the same, we then look at the minutes, and the largest one goes on top. If those are the same as well, we look at the seconds and do the same thing.
Once we know which angle is larger, we place the degrees under the degrees, the minutes under the minutes, and the seconds under the seconds so we can subtract them correctly.
The angles we will subtract are 245° 12′ 25″ and 128° 9′ 57″. Which one will we place on top? That’s right, the first one since it has the larger degree.
Once we have placed the angles correctly, we subtract the seconds first, then the minutes, and finally the degrees.
In the seconds column, we need to subtract 57 from 25, which isn’t possible. So, we take 1 minute off from the minutes column and give it to the seconds. This gives us 11 minutes and 85 seconds. How did we get to 85? Because 1 minute is 60 seconds, and 60 + 25 equals 85.
Next, we subtract the minutes. If the top number is less than the bottom, we subtract one from the degrees and add 60 to the minutes, then continue with the subtraction.
Now we can subtract! Here we go:
85 seconds – 57 seconds equals 28 seconds.
11 minutes – 9 minutes equals 2 minutes.
245 – 128 equals 117°.
So our final result will be 117° 2′ 28″. Great job! Wasn’t it simpler than it looked? You’ll see how quickly you can get the hang of it.
Now it’s time to practice!
[Music]
We’ve learned so much in just one video. Did you know there are many more videos? Imagine how much you could learn! Subscribe to the Smile and Learn educational channel to learn and have fun at the same time.
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This version maintains the educational content while removing any informal language or distractions.
Angle – A figure formed by two rays with a common endpoint called the vertex. – In our math class, we learned how to measure the angle between two lines using a protractor.
Subtract – To take away one number from another to find the difference. – When you subtract 30 degrees from 90 degrees, you get a 60-degree angle.
Degrees – A unit of measurement for angles, where a full circle is 360 degrees. – The teacher showed us how to measure angles in degrees using a protractor.
Minutes – A smaller unit of angle measurement, where one degree is divided into 60 minutes. – We learned that an angle of 45 degrees and 30 minutes is slightly larger than 45 degrees.
Seconds – An even smaller unit of angle measurement, where one minute is divided into 60 seconds. – The angle was so precise that it was measured in degrees, minutes, and seconds.
Borrow – In subtraction, to take one unit from the next higher place value to make subtraction possible. – When subtracting angles, sometimes you need to borrow from the degrees to subtract the minutes.
Compare – To examine the differences between numbers or angles to determine which is larger or smaller. – We had to compare two angles to see which one was larger.
Arrange – To put numbers or angles in a specific order, such as from smallest to largest. – Our task was to arrange the angles in order from smallest to largest.
Sexagesimal – A numeral system with a base of 60, used in measuring angles, time, and geographic coordinates. – The sexagesimal system helps us understand angles in degrees, minutes, and seconds.
Practice – To do something repeatedly to improve skill or understanding. – We need to practice measuring angles to become better at using a protractor.
