Question

resolva as equações do primeiro grau ?​

Answer 1

Explicação passo-a-passo:

a)

{x + y = 10

{x - y = 4

x + y + x - y = 10 + 4

2x = 14

x = 14/2

x = 7

x + y = 10

7 + y = 10

y = 10 - 7

y = 3

S = {(7 ; 3)}

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b)

{x + y = 6

{x - y = 2

x + y + x - y = 6 + 2

2x = 8

x = 8/2

x = 4

x + y = 6

4 + y = 6

y = 6 - 4

y = 2

S = {(4 ; 2)}

•••••••••••••••••

c)

{x + y = 12

{x - y = 4

x + y + x - y = 12 + 4

2x = 16

x = 16/2

x = 8

x + y = 12

8 + y = 12

y = 12 - 8

y = 4

S = {(8 ; 4)}

•••••••••••••••••

d)

{x + y = 9

{x - y = 5

x + y + x - y = 9 + 5

2x = 14

x = 14/2

x = 7

x + y = 9

7 + y = 9

y = 9 - 7

y = 2

S = {(7 ; 2)}