if the lengths of the sides will be: 4x,9x and 10x.
perimeter of a triangle is the sum of all sides.
Therefore; we can suggest the following equation:
4x+9x+10x=115
23x=115
x=115/23
The lengths of the sides will be:
4x=4(115/23)=20
9x=9(115/23)=45
10x=10(115/23)=50
Answer: the lengths would be: 20 cm, 45 cm and 50 cm.