How to find the area and circumference of a circle
A circle is the set of all points in a plane that are a fixed distance from a fixed point, called the center, and are separated by a fixed distance, called the radius. A circle's perimeter, or distance around it, is its circumference (C). A circle's area (A) is the amount of space it occupies or the area it encompasses.
Calculate the area of a circle by using the formula:
Step 1. The area
of a circle can be determined using two distinct formulas based on the diameter
or radius:
A =π
These
equations are essentially the same because the radius of a circle is equal to
half of its diameter. The area can be measured in feet squared (
Step
2. Recognize the various components of
the formula. The radius, diameter, and circumference of a circle are the three
components needed to calculate its circumference. The radius and diameter are
proportional: the radius is half the diameter, and the diameter is double the
radius.
A circle's
radius (r) is the distance between one point on the circle and its center.
A circle's
diameter (d) is the distance between one point on the circle and another
exactly opposite it, measured through the center.
The
number 3.14159265..., an irrational number with neither a final digit nor a
recognized pattern of repeated digits, shows the ratio of circumference divided
by diameter.
Step
3.Calculate the circle's radius or
diameter. Place one end of a ruler on one side of the circle and the other end
on the other side of the circle, passing through the center point. The radius
is the distance from the circle's center, while the diameter is the distance from
one end to the other.
The
radius or diameter is provided radius=4m diameter=6m
Step
4. Solve the problem by putting in the
variables. You can put the radius and/or diameter of the circle into the
relevant equation once we've determined the radius and/or diameter.
Use A =π
Example: What is the area of a 4 meter radius circle?
By putting the values:
A
=π
Variables to the plugin: A=π
Radius
is squared: The
Multiply by pi (π) if we want to get a more complicated answer
A=π
Example:
What
is the area of a circle with a diameter of 8 meters?
By putting the values
A
=π
Variables to the plugin: A=π
By
multiplying the diameter by two, you can arrive at the following result:2
= 64is the squared result.
Multiply by pi (π) if we want to get a more complicated answer
A=π
Calculate the Area and Circumference
of a circle with variables:
Step 1.Calculate the circle's radius
or diameter. Some issues will offer you a variable radius or diameter, such as
r = (y+ 2) or d = (y+ 4). You can still solve for the area or circumference in
this scenario, but your final solution will include that variable. As specified
in the problem, write down the radius or diameter.
As an illustration: Determine the
circumference of a circle with (y = 2) radius.
Step 2.With the information
provided, write the formula.
Regardless of whether you're solving
for area or circumference, the essential steps of filling in what you know will
remain the same. Make a note of the area or circumference formula, and then put
in the variables.
As an illustration: Compute the circumference of a circle
with a radius of (y +2) and
a diameter of (y + 4).
Write the formula: C =2πr
Fill in the details with the provided data: C=2π(y+2)
Step 4.Solve the problem as if the
variable was a number. You can now answer the problem normally, using the
variable as if it were a number. To simplify the final answer, you may need to
apply the distributive property.
As an illustration: Calculate the circumference of a circle
with a radius of y=1
C = 2πr=2π(y +2) = 2πy +2π(2) = 6.28y + 12.56
You can insert the value of "y" in the above
equation to obtain a whole number solution.
C = 6.28 (1) + 12.56 =18.84 units