Question

resolva os sistemas :

a) {x+2x=34
{x+4y=4

b) {3x+y=25
{x-y= -5

c) c){x-y=5
{x+7=7

d) {x-y=2
{2x+y=4

Answer 1

c) x=5+y

x+7=7

5+y+7=7

y=7-7-5

y=7-13

y=-5(-1)

y= 5

x=5+y

x=5+5

x=10

d)x=2+y

2x+y=4

2(2+y)+y=4

4+2y+y=4

2y+y=4-4

3y=0

y=0

x=2+y

x=2+2

x=2