Q8 of 69 Page 250

An isosceles triangle has perimeter 30cm and each of its equal sides is 12cm. Find the area of the triangle.

It is given in the question that,

Equal sides of isosceles triangle = a = b = 12 cm


Also, perimeter = 30 cm


We know that perimeter of triangle = Sum of all sides


(a + b + c) = 30 cm


12 + 12 + c = 30


24 + c = 30


c = 30 – 24


= 6 cm


Hence, s =


s =


s = 15 cm


∴ Area of triangle =


=


=


= 9 cm2


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Find the area of ABC in which BC = 8cm, AC = 15cm and AB = 17 cm. Find the length of altitude drawn on AB.

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The perimeter of an isosceles triangle is 32cm. The ratio of one of the equal side to its base is 3: 2. Find the area of the triangle.

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Given a ABC in which

I. A, B and C are in the ratio 3: 2 :1.


II. AB , AC and BC are in the ratio 3 : 3 : 2 3 and AB = 3 3 cm.


Is ABC a right triangle?


The question give above has two Statements I and II. Answer the questions by using instructions given below:


(a) If the question can be answered by one of the given statements only and not by the other.


(b) If the question can be answered by using either statement alone.


(c) If the question can be answered by using both the statements but cannot be answered by using either statement.


(d) If the question cannot be answered even by using both the statements together.