Question

Which triangle is possible?

3 ft, 4ft, and 5ft 4yd, 5ft, and 10yd
3 ft, 3 ft, and 7 ft.
4 in, 4 in, and 8 in

Answer 1

(a) 3 ft, 4 ft, 5 ft

Explanation:

The triangle inequality requires the sum of the two short sides exceed the long side.

__

a) 3 ft + 4 ft = 7 ft > 5 ft . . . . . triangle is possible

b) 4 yd + 1 2/3 yd = 5 2/3 yd < 10 yd . . . . not a possible triangle

c) 3 ft + 3 ft = 6 ft < 7 ft . . . . not a possible triangle

d) 4 in + 4 in = 8 in . . . . not a possible triangle (not greater than 8 in)

__

The first set of side lengths can form a triangle: 3 ft, 4 ft, 5 ft.