Question

Which of the following combination of sides (in cm) helps to construct a triangle?

• A. 3, 6, 9
• B. 4, 4, 8
• C. 2, 4, 8
• D. 7, 8, 9

Answer 1

The correct option is D 7, 8, 9

A triangle can be constructed only if, the length of any side of a triangle lies between the difference and sum of the other two sides.
$2,4,8$ can't be the sides of a triangle because $2+4<8$.
$4,4,8$ can't be the sides of a triangle because $4+4=8$.
$7,8,9$ can be the sides of a triangle because
$7+8>98+9>77+9>8$

$3,6,9$ can't be the sides of a triangle because $3+6=9$.

Only $7,8,9$ can form a triangle out of the given triplets.