The sum of the perimeters of two similar polygons is equal to 699 dm

The sum of the perimeters of two similar polygons is equal to 699 dm, and their smallest respective sides are 8 and 15 dm. define the perimeters of these polygons.

Let x dm be the perimeter of the small polygon;
(499-x) dm – the perimeter of the large polygon;
since the corresponding sides of the polygons are known and the polygons are similar, you can make the proportion:
8/15 = x / (699-x);
15x = 8 (699’s);
15x = 5592-8x;
23x = 5592;
x = 5592/23;
x = 243.13 … (dm) – the perimeter of the small polygon.
699-243.13 = 455.87 … (dm) – the perimeter of the large polygon.
Answer: 243.13 … dm; 455.87 … dm.