Question

Lengths of two sides of an isosceles triangle are 5 cm and 8 cm, find the perimeter of the triangle.​

Answer 1

Answer:

Let A triangle XYZ

in which XY= XZ=5cm

and YZ= 8cm

therefore, perimeter= XY+YZ+ZX= (5+5+8)cm=18cm

Answer 2

⠀⠀ıllıllı uoᴉʇnloS ıllıllı

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Since the lengths of any two sides of an isosceles triangle are equal, then

Case I:

The three sides of the triangle are 5 cm, 5 cm and 8 cm.

Perimeter of the triangle =

➠ 5 cm + 5 cm + 8 cm = 18 cm

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Case II:

The three sides of the triangle are 5 cm, 8 cm and 8 cm.

Perimeter of the triangle =

➠ 5 cm + 8 cm + 8 cm = 21 cm

• Hence, the required perimeter is 18 cm or 21 cm.

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Additional Information:

What is Isosceles triangle?

• Isosceles triangle are those triangles whose any two sides are equal.

What is Triangle?

• Triangle is a closed figure which has three sides, three vertices and three angles.
• The sum of three angles of a triangle is equal to the 180 degree.

How many types of triangle?

• There are three types of triangle on the basis of sides are:

(1) Scalene Triangle

(2) Isosceles Triangle

(3) Equilateral Triangle

• There are three types of triangle on the basis of angles are:

(1) Acute Angled Triangle

(2) Right Angled Triangle

(3) Obtuse Angled Triangle

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