Question

Sa se afle x si y stiind ca sunt invers proportionale cu 2 si 3 si ca 4x+9y-60

Answer 1

x/1/2=x1/3=k
4x+9y=60
2x=3y=k
2x=k. x=k/2
3y=k. y=k/3
4•k/2+9•k/3=60
2k+3k=60
5k=60
k=60:5
k=12

x=k/2. x=12/2. x=6
y=k/3. y=12/3. y=4
proba:4×6+9×4=60
24+36=60
60=60