Question

gasiti trei numere x,y z direct proportionale cu 2,5 si 3 astfel incat 4x-y +2z =783

Answer 1

x/2=y/5=z/3=k
x/2=k => x=2k
y/5=k => y=5k
z/3=k => z=3k
4x-y+2z=783
4×2k-5k+2×3k=783
8k-5k+6k=783
3k+6k=783
9k=783
k=783:9
k=87
x=2×k=2×87=174
y=5×k=5×87=435
z=3×k=3×87=261

Answer 2

{x,y,z} d.p. { 2,5,3}
4x-y +2z = 783
Rezolvare :
Aplici teorema cu k .
x=2k
y=5k
z=3k
4×2k -5k + 2 × 3 k = 783
8k-5k+6k = 783
3k+6k =783
9k = 783 | : 9
k =87
x= 2 × 87 =174
y=5×87 = 435
z=3×87=261