Formula for Area of ​​a Circle Complete Discussion

Math formulaThe formula for the area of ​​a circle is the material that we will discuss this time. Not only a discussion of the formula for the area of ​​a circle, in this article I will also give examples of questions about circles so that you have an image of how to answer questions about circles with the formulas that have been given. Don’t forget at the end of the article I also attached some tips and tricks that you can apply when working on questions about circles. Alright, let’s just study the formula for the area of ​​a circle and an example of the problem below:

This is the material that we will discuss this time. The formula for the area of ​​a circle is a complete discussion
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Also read: How to Calculate the Area of ​​a Triangle Formula

Example Problems and Formulas for Area of ​​a Circle

Circle Area Formula

We can find the area of ​​a circle using the formula below:

Area of ​​Circle = x radius2 (π x r2)

phi(π) = 3, 14 or 22/7
r = radius = 1/2 diameter

Example questions about the area of ​​a circle:

Example question 1:
If there is a circular fish tank with a diameter of 56 m, what is the area of ​​the fish tank?

How to answer:
We must first find out what the radius of the tub is:
Body radius = 1/2 x 56 = 28 m

Area of ​​the tub = x radius2
Then the area of ​​the tub = 22/7 x 28 x 28
The area of ​​the tub = 2464m2

Example question 2:
There is a playground with a semicircle shape. The diameter of the playground is 42 m, what is the total area of ​​the playground?

How to answer:
First find the radius = 1/2 x 42 = 21m
Area of ​​semi circle = 1/2 x x radius2
Playground area = 1/2 x 22/7 x 21 x 21
Area of ​​playground = 1386 / 2 = 693m2

Tips and tricks in calculating the formula for the area of ​​a circle

First:
When you want to calculate the formula for the area of ​​a circle, determine the value of pi () which corresponds to the value of the radius of the circle. For example, to calculate the radius whose value is 7 and its multiple (14, 21, 28, 35, 49, etc.) then you should use phi = 22/7. You can also use the value of phi 22/7 in calculating the radius whose value is in the form of integers. Meanwhile, to calculate the area of ​​a circle whose radius is expressed in decimal form, you better specify phi in decimal form as well, namely = 3.14. This will make it easier for you to calculate the area of ​​a circle.

Second:
You should not be too hasty when you want to determine the value of r2, just let the calculation be in the form rxr who knows later there will be values ​​that can be removed or crossed out. For example, when you calculate r = 49, don’t rush to calculate it to be r2 = 492(2401)

Third:
Pay close attention to the unit of length in the nature of the problem. Usually the response depends on the unit of length used in the problem.

That’s the description of formula for area of ​​a circle along with examples of questions as well as tips and tricks for dealing with problems relating to the calculation of the area of ​​a circle. if you pay attention and read carefully every explanation that I have given above, I am sure from now on you will be easier and more reliable in answering and calculating the area of ​​a circle in the questions given at school. See you again in the next article.