Question

ME AJUDEM POR FAVOR!!


obs:somente as questões a,b,c,d,e.​

Answer 1

Resposta:

Explicação passo a passo:

a.

x+y=22

x-y=8

_____

2x+0=30

2x=30

x=30/2

x=15

x+y=22

15+y=22

y=22-15

y=7

b.

2x+y=26

x-y=4

______

3x+0=30

3x=30

x=30/3

x=10

2x+y=26

2.10+y=26

20+y=26

y=26-20

y=6

c.

3x+y=-5 (2)

5x-2y=-1

6x+2y=-10

5x-2y=-1

_______

11x+0=-11

11x=-11

x=-11/11

x=-1

3x+y=-5

3.-1+y=-5

-3+y=-5

y=-5+3

y=-2

d.

x+2y=-4

3x-2y=20

________

4x+0=16

4x=16

x=16/4

x=4

x+2y=-4

4+2y=-4

2y=-4-4

2y=-8

y=-8/2

y=-4

e.

x+3y=3

2x-y=1,8 (3)

x+3y=3

6x-3y=5,4

_________

7x+0=8,4

7x=8,4

x=8,4/7

x=1,2

x+3y=3

1,2+3y=3

3y=3-1,2

3y=1,8

y=1,8/3

y=0,6

f.

x/5=10-y/2

x-y=8

x=5(10-y/2)

x=50-5y/2

50-5y/2-y=8

100/2-5y/2-2y/2=16/2 [corta denominador 2]

100-5y-2y=16

-7y=16-100

-7y=-84 (-1)

7y=84

y=84/7

y=12

x-y=8

x-12=8

x=8+12

x=20