Question

va roooooooooooooooog

Answer 1

a) x+y = 10 / 2
x-y = 2

2x +2y = 20
x - y = 2

3x + y = 22
x-y=2 => x = 2-y => 3(2-y) + y = 22 => 6-3y+ y= 20 => -2y = 20-6 => -2y = 14 => y = -7

x= 2-y => x= 2-(-7) => x = 14

Answer 2

1)

x+y=10

x-y=2

x=10-y

inlocuim in a 2 a relatie:

10-y-y=2⇒-2y=-8⇒y=4

x+4=10⇒x=10-4⇒x=6

2)

4x=8+5y⇒x=8+5y / 4

3(8+5y / 4) +1=y+6

amplificam cu 4 si aducem la acelasi numitor

3(8+5y)+4=4(y+6)

24+15y+4=4y+24

15y-4y=24-24-4

11y=-4

y=-4/11

inlocuim in prima relatie:

3x+1=-4/11+6

33x+11=-4+66

33x=-4+66-11

33x=51 simplificam cu 3

11x=17

x=17/11

cred ca am facut bine