Q. 141
The lengths of two sides of an isosceles triangle are 9 cm and 20 cm. What is the perimeter of the triangle? Give reason.
Answer :
Formula Used/Theory:-
Perimeter = sum of all sides of triangle
There can be 2 cases
(i) If equal sides in isosceles triangle is equal to 9cm
Then;
Perimeter = 9cm + 9cm + 20cm
= 38cm
(ii) If equal sides in isosceles triangle is equal to 20cm
Then;
Perimeter = 20cm + 20cm + 9cm
= 49cm
∴ perimeter of triangle can be either 38cm or 49cm
Result:- Perimeter of triangle is either 38cm or 49cm.
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