Question

The number of integer sided triangles whose two sides are 3 cm, 8 cm is
(A)5 (B)6 (C)7 (D)8

Answer 1

There are 5 such triangles possible. (A)

Answer 2

let the sides of the triangle be a, b, and c respectively.
     a = 3 cm          b = 8 cm

      | a - b | <  c <  | a + b |
       5 cm  < c < 11 cm

       c = 6, 7, 8, 9, and 10 cm.

  Hence there are 5 triangles possible.  as c can only be of length = integer.