ab+bc+ac=16,8
ab/bc=7/5
bc/ac=3/4
Решаем
ab=7bc/5
ac=4bc/3
7bc/5+bc+4bc/3=16,8
(21+15+20)bc=16,8*15
bc=252/56=4,5 метра
ab+bc+ac=16,8
ab/bc=7/5
bc/ac=3/4
Решаем
ab=7bc/5
ac=4bc/3
7bc/5+bc+4bc/3=16,8
(21+15+20)bc=16,8*15
bc=252/56=4,5 метра