Question

Exercitiu 1 si 2 complet. Va rog

Answer 1

1.
(12x-5y)/3x=2/3
4-5y/3x=2/3
5y/3x=4-2/3
5y/3x=10/3    
30x=15y
2x=y
x/y=1/2

(x²+xy)/y²=x²/y²+xy/y²=(x/y)²+x/y=(1/2)²+1/2=1/4+1/2=3/4

2.
(x-1)/(1+1/2)=(7/3-1)/(3-3/2)
(x-1)/(3/2)=(4/3)/(3/2)
2(x-1)/3=4/3×2/3
2(x-1)/3=8/9
(x-1)=3×8/2×9
x-1=4/3
x=4/3+1=7/3


b)
(2x+1)/(4x+3)=1/3
4x+3=6x+3
4x=6x
x=0