Question

método de substituição

2x+4y=2
x-y=5

x+4=y
2x-y=3

(1°,2° e 3° parte) ​

Answer 1

Resposta:

a) 2x+4y=2

x-y=5 --> X=5+y

2x+4y=2

2(5+y)+4y=2

10+2y+4y=2

6y=-10+2

6y=-8

y=-8/6 ---> -4/3

2x+4y=2

2x+4.-8/6=2

2x-32/6=2

12x-32=12

12x=12+32

12x=44

x=44/12 --> 22/6 --> 11/3

b)x+4=y ---> x=y-4

2x-y=3

2(y-4)-y=3

2y-8-y=3

y=8+3

y=11

x+4=y

x+4=11

x=11-4

x=7