The lengths of the sides of a triangle are in ratio 5:6:7 describe the length of the longest side if the perimeter is less then 54

The sides of this triangle are 5x, 6x abd 7x,

The perimeter of a triangle is the sum of all sides

We can suggest this inequation:

5x+6x+7x<54

18x<54

x<54/18

x<3

Therefore the lenght of the longest side would be:

7x< (7*3)

7x<21

Answer: the lenght of the longest side would be <21