Question

consists of 50 terms of which the third term is 12 and the last term is 106 find the 25th term​

Answer 1

Answer:

Answer:

Given :-

The semi-perimeter of a triangle is 10 cm. One of its side is 5 cm and 7 cm respectively.

To Find :-

What is the third side of a triangle.

Formula Used :-

$\sf\boxed{\bold{Semi-perimeter\: =\: \dfrac{Sum\: of\: all\: sides\: of\: triangle}{2}}}$

Solution :-

Let, the third side of a triangle be c cm.

Given :

First side (a) = 5 cm

Second side (b) = 7 cm

According to the question by using the formula we get,

⇒ $\sf 10 =\: \dfrac{5 + 7 + c}{2}$

⇒ $\sf 10 =\: \dfrac{12 + c}{2}$

⇒ $\sf c =\: 2 \times 10 - 12$

⇒ $\sf c =\: 20 - 12$

➠ $\sf\bold{\pink{c =\: 8\: cm}}$

$\therefore$ The third side of a triangle is 8 cm .