Question

Ajuda aqui rapido


a)X+ 2y = 8 3x-4y=4

b)3x+ 2y=6 2x+3y=5

Answer 1

Resposta:

a) x = 4 | y = 2

b) x = 8/5 | y = 3/5

Explicação passo-a-passo:

a) x + 2y = 8

3x - 4y = 4

x = 8 - 2y

3(8 - 2y) - 4y = 4

24 - 6y - 4y = 4

24 - 10y = 4

- 10y = 4 - 24

10y = 20

y = 20:10

y = 2

x = 8 - 2y

x = 8 - 2.2

x = 8 - 4

x = 4

b) 3x + 2y = 6 .(2)

2x + 3y = 5 .(3)

6x + 4y = 12

6x + 9y = 15

6x = 12 - 4y

(12 - 4y) + 9y = 15

12 + 5y = 15

5y = 15 - 12

5y = 3

y = 3/5

6x + 9y = 15

6x + 9(3/5) = 15

6x + 27/5 = 15

6x = 15 - 27/5 .(5)

30x = 75 - 27

30x = 48

x = 48/30

x = 8/5