what is the L of the longest side

Question

lengths of the sides of a triangle, when measured in meters, are consecutive odd integers. What is the length of the longest side if the perimeter of the triangle is

21 m?

I had got 10

Answer 1

The longest side can't be 10 meters because 10 is not an odd integer.

.

Perimeter = Side1 + Side2 + Side3

Side2 = Side1 + 2      (next odd integer above Side1)

Side3 = Side1 + 4      (next odd integer above Side2)

Perimeter = Side1 + Side1 + 2 + Side1 + 4

Perimeter = 3*Side1 + 6

Perimeter = 21

3*Side1 + 6 = 21

3*Side1 = 15

Side1 = 5

Side2 = 7

Side3 = 9

Check:  5 + 7 + 9 = 21, good.

Answer:  The longest side is 9 meters.