Question

va rog imi treb rezolvarea intr-o ora cel mult 2 ore repede​

Answer 1

Răspuns:

a) 7x/9-2y/3=0 adica 7x-6y=0

7x/9+y/3=1/3 adica 7x+3y=3

x= 6y/7

7*6y/7+3y=3 rezulta 9y = 3 rezulta y = 1/3 iar x = 6/7*3=2/7

b) x/6+y/5=1/45 adica 15x+18y = 1  

x/2+y/5 = 1/15 adica 15x +6y = 1

x = 1-18y/15

1-18y+6y = 1 rezulta y = 0 iar x = 1

c) x/2+5y/6= 1/3 adica 15x+25y=10 rezulta 3x+5y=2 rezulta x =2-5y/3

6x/25-y/5=1/3 adica 18x-15y=25

18(2-5y/3)-15y=25

12-30y-15y = 25 rezulta 45y = -13 rezulta y = -13/45

x=(2+5*13/45)/3=(18/45)/3=18/45*3=2/15

d) 2x/3-5y/7=1/9 adica 42x-45y=5 rezulta x = 5+45y/42

x/2+11y/13=2/5 adica 65x+110y=52 65(5+45y)/42+110y=52

325+2925y+4620y= 2184 rezulta 7545y = 1859 rezulta y = 1859/7545 iar x = (5+45*1859/7545)/42

Explicație pas cu pas: