Question

A student know that one side of a triangle is 19 cm. Which set of two sides are possible for the lengths of the other two sides of this triangle?

7 cm and 11 cm

8 cm and 8 cm

7 cm and 12 cm

5 cm and 16 cm

Answer 1

D. 5 cm and 16 cm

Explanation:

In a triangle, the sum of the lengths of any two sides must be greater than the length of the third side.

The sum of the two lengths given must be greater than 19 cm.

A.

7 cm + 11 cm = 18 cm

18 cm < 19 cm

No triangle

B.

8 cm + 8 cm = 16 cm

16 cm < 19 cm

No triangle

C.

7 cm + 12 cm = 19 cm

19 cm = 19 cm

No triangle

D.

5 cm + 16 cm = 21 cm

21 cm > 19 cm

There is a triangle.