Perimeter of a Triangle Calculator: Quick & Easy Solution

Perimeter of a Triangle Calculator

This Perimeter of a Triangle Calculator is very easy to use for everyone. And gives immediate response to Perimeter of a Triangle calculations.

Perimeter of a Triangle Calculator

Solve triangle by: Select metric: Side A: Side B: Side C:

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What is Perimeter of a Triangle?

Here we are going to understand the perimeter of a triangle. This is a simple method because you have to apply its formula, which is P = A + B + C. Now what is this? A triangle has three parts (sides), which are A, B, and C. Here A is 4 cm; after that, we will keep B 4 cm and C 4 cm, which means all three sides are of the same length. What we have to do here is A + B + C. Here we have to add the length of the side of the triangle. Then we will get its perimeter. What is a perimeter? See here that the overall border of the triangle is its border; we call it the perimeter. We can also call it circumference; if it is a circle, then we can also call it its circumference; otherwise, we call it perimeter. So see here what will be our A = 4 cm, B = 4 cm, and C = 4 cm. So what will happen here? 4 + 4 + 4 = 12 cm. Here, the perimeter of the triangle will be 12 cm. An image is given below to understand the example.

Perimeter of a Triangle Formula

Curious about the distance around a triangle? The Perimeter of a Triangle Calculator is your shortcut. The formula is simple – add up the lengths of all three sides. It’s like measuring the edges and the joint them up. The formula for the perimeter of a triangle T is

P = side a + side b + side c

An image is given below to understand.

Guidelines for Triangle Solving

P = side a + side b + side c

An image is given below to understand.

SSS (Side-Side-Side) Calculation Formula and Calculation

Calculation Formula - Add up the lengths of all three sides of the triangle.

�_{� � �} = � + � + �

Calculation Example - Here

�

�

, and

�

are the lengths of the three sides of the triangle.

Let's say we have a triangle with side lengths

� = 5

� = 7

, and

� = 9

units.

�_{� � �} = 5 + 7 + 9 = 21

So, the perimeter of the triangle is

21

units.

SAS (Side-Angle-Side) Calculation Formula and Calculation

Calculation Formula - Add the lengths of the two known sides and multiply the sum by

\frac{1}{2}

times the sine of the included angle, then add the length of the remaining side.

�_{� � �} = (� + �) + � \cdot \sin (�)

Where

�

and

�

are the lengths of the known sides,

�

is the length of the unknown side, and

�

is the measure of the included angle.

Calculation Example - Suppose we have a triangle with side lengths $� = 6$ , $� = 8$ , and an included angle $� = 4 5^{\circ}$ , and we want to find the length of side $�$ .

c² = 6² + 8² − 2 × 6 × 8 × cos(45°)

c² = 36 + 64 − 96 × cos(45°)

c² = 100 − 96 × 7071...

c² = 100 − 67.8816... = 32.1184...

c = √32.1184...

c = 5.6673...

c = 5.6673 to 2 decimal places ( length of side

c

. )

perimeter = A+B+C

perimeter = 6+8+5.6673 = 19.6673 units .

so, the perimeter of the triangle is approximately 19.6673 units. ( 19.7 units)

$�_{� � �} = (6 + 8) + � \cdot \sin ($

SSA (Side-Side-Angle) Formula and Calculation

Calculation Formula - Use the Law of Sines to find the length of one of the unknown sides, then calculate the perimeter using the lengths of all three sides.

PSSA=a+b+c

�_{� � �} = � + � + �

ASA (Angle-Side-Angle) Formula and Calculation

Calculation Formula - This situation uniquely determines a triangle, so the perimeter is simply the sum of all three sides.

PASA=a+b+c

Calculation Example - Given a triangle with angles

� = 3 0^{\circ}

� = 6 0^{\circ}

, and side

� = 8

units, we can calculate the lengths of sides

�

and

�

using the Law of Sines or the Law of Cosines. Once all three sides are known, we can calculate the perimeter straightforwardly as shown in the previous examples.

�_{� � �} = � +

Examples: Calculate a Triangle's Perimeter

some examples.
Example 1

Side A: 5 units
Side B: 8 units
Side C: 6 units
Using the Perimeter Formula: 5 + 8 + 6 = 19 units
So, the perimeter is 19 units.
Example 2

Side A: 12 cm
Side B: 12 cm
Side C: 12 cm
All sides are equal, making it an equilateral triangle.
Perimeter Formula: 12 + 12 + 12 = 36 cm
The perimeter is 36 cm.
Example 3

Side A: 3 in
Side B: 4 in
Side C: 5 in
It’s a right triangle, following the 3-4-5 rule.
Perimeter Formula: 3 + 4 + 5 = 12 in
The perimeter is 12 in.

Frequently Asked Questions (FAQ)

1. What is the formula for the perimeter of a triangle?
Perimeter P = a + b + c for which the lengths of the sides of any triangle are given as a, b, and c.
2. Is there a triangle for which the Perimeter of a Triangle Calculator will fail?
Well, using this calculator counts for all shapes of any triangle whether equilateral, isosceles, or scalene.
3. Is it somehow known what type of triangle it is to use a calculator?
No, you don’t have to know what type of triangle it is. You can enter all three sides, and the calculator will find the perimeter.
4. What inputs does a Perimeter Calculator accept in a triangle?
The calculator is set to accept units such as meters, centimeters, millimeters, and feet or inches. To get the right answer, ensure that all sides are measured in the same unit.
5. What if the triangle has one missing side?
You must be aware of the triangle’s three sides to compute its perimeter. The Pythagorean theorem (for right triangles, for example) may be used to identify the missing side if one of the side lengths is missing.
6. Is the Triangle Perimeter Calculator free to use?

Yes, most of the free online calculators about finding the perimeter of a triangle are free and can be used unlimited times without charge.
7. Accuracy of the Perimeter of a Triangle Calculator
A perimeter calculator makes the perimeter highly accurate. If you provide the key to the correct measurements, the calculator will give you the exact answer.
8. Can I use Perimeter of a Triangle Calculator from my smartphone?
Of course, Perimeter of a Triangle Calculator is very responsive and mobile device friendly, so very handy for computations on the go.