Question

aflati nr x si y stiind ca sunt direc proportionale cu nr 2,5 si 1,5 si ca 3x+7y=66

Answer 1

{x; y} d.p. {2,5; 1,5}  si 3x+7y=66
2,5=25/10=5/2
1,5=15/10=3/2

x/(5/2)=y/(3/2)=k
x=5k/2
y=3k/2
3x+7y=3·5k/2 + 7·3k/2
36k/2=66
18k=66=> k=11/3
a=5k/2=5·11/6
a=55/6
b=3k/2=3·11/6
b=11/2