Question

Daca fractia 8x-5ysupra4x+5y este egala cu 1supra3,stabiliti atunci daca fractia 6x+5ysupra12x-5y este subunitara,supraunitara sau echiunitara?
Faceti va rog rezolvarea completa,dau 21 puncte.

Answer 1

(8x - 5y)/(4x + 5y)= 1/3
3(8x - 5y) = 4x + 5y
24x - 15y = 4x + 5y
20x = 20y
x = y      (6x +5y)/(12x - 5y)    11x/7x = 11/7  = fr. supraunitara

Answer 2

8x-5y/4x+5y=1/3⇒3(8x-5y)=(4x+5y)⇒24x-15y=4x+5y⇒24x-4x=15y+5y=20x=20y⇒20y/20x=y/x
6x+5y/12x-5y=6x+5y=12x-5y⇒5y+5y=12x-6x⇒10y=6x⇒fractie  supraunitara