Question

stabileste care dintreurmatoarele sisteme sunt echivalente
a) x-y=3
x+y=-1
b)2x-5y-3=1
-x+6y-2=0
c)x+y-3=0
x=6y-2

Answer 1

Răspuns:

a) x=y+3

y+3+y=-1

2y=-4

y=-2

x+2=3

x=1

b) 2x-5y=4

-x+6y=2/*2 => -2x+12y=4

(+) / 7y=8

y=7/8

2x-5*7/8=4

16x-35= 32

16x= 67

x=67/16

c) x+y=3

6y-2+y=3

7y=5

y=5/7