Question

Two sides of a triangle are 18cm and 13cm. the perimeter of triangle is 42 cm. Find it's third sides. ​

Answer 1

Answer:

The side are 11 m.

Step-by-step explanation:

Let the side are a, b and c

Two sides of a triangle are 18cm and 13cm.

The perimeter of triangle is 42 cm.

The perimeter of triangle =sum of all sides

                 $a+b+c=42\\ \\ 18+13+c=42\\ \\ 31+c=42\\ \\ c=42-31=11$

The third side are 11 cm.

Answer 2

Answer :

The light of Third side of Triangle is 11cm

Step-by-step Explanation :

Given : Two sides of a triangle are 18cm & 13cm

Perimeter of Triangle is 42cm

To find : Third side of Triangle = ?

We know that,

Perimeter of triangle = Sum of all the sides of triangle

So, substituting the given value in above formula,

We get,

Perimeter = side1 + side2 + side3

42 = 18 + 13 + side3

42. = 31 + side3

42 - 31 = length of 3rd side of triangle

11cm = length of 3rd side of Triangle

Hence The light of Third side of Triangle is 11cm