1)
b) y-4/5=7/3 aducand la acelasi numitor: 15*y-3*4=5*7 15y=47 y=47/15
c)4/5=3z-2/9 aducand la acelasi numitor: 9*4=45*3z-5*2 36=135z-10 z=46/135
d) 4t+5/3=7/2 aducand la acelasi numitor: 6*4t+2*5=3*7 24t+10=21 t=11/24
e) 5x+1/2=7/3 aducand la acelasi numitor: 6*5x+3=2*7 30x+3=14 x=11/30
la fel toate...
2)
x/y=4/9 deci, x=4y/9
atunci: 3x+2y/(5x) +y=3*4y/9 + 2y/(5*4y/9) + y=4y/3 + (2y*9)/(5*4y) +y=4y/3+9/10+y=
=(40y+27+30y)/30=( 27+70y)/30
dar, cred ca ai scris gresit fractia a doua adica (3x+2)/(5x+y) pentru ca altfel, raspunsul depinde de o necunoscuta
daca e asa cum cred la numarator: 3x+2y=3*4y/9+2y=4y/3+2y=(4y+6y)/3=10y/3
la numitor: 5x+y=5*4y/9+y=(20y+9y)/9=29y/9
deci, (3x+2)/(5x+y)=(10y*9)/(3*29y)=30/29
nu mai continui pana nu inteleg exact care sunt fractiile