Question

a/3 = b/5 = c/7 ;; ab+bc+ca= 7100 ;; a=? b=? c=?​

Answer 1

Răspuns:

a/3=b/5=c/7=k => a=3k

b=5k

c=7k

a*b+b*c+c*a=7100

3k*5k+5k*7k+7k*3k=7100

15k^2+35k^2+21k^2=7100

71k^2=7100

k^2=7100/71

k^2=100

k=radical din 100

k=10

a=3k= 3*10=30

b=5k= 5*10=50

c=7k= 7*10=70