Question

URGRNTE!!!!!

COM CALCULO!!!!!​

Answer 1

Resposta:

a ) x-y = 3 x= 3 + y x = 3+1 x=4

2x + y = 9

2 ( 3 + y ) + y = 9

6 + 2y + y = 9

3y = 9 - 6

y = 3/3

y = 1

b) x = 3y

x+ 2y =10

3y + 2y =10 x = 3 × 2

5y = 10 x = 6

y = 10 /5

y= 2

c) x+ y = 10 x=10-y

2x - y = 8 x = 10 - 4

x = 6

2 (10-y)-y = 8

20 - 2y - y = 8

- 3y = 8 - 20

-3y = -12 (-1)

3y = 12

y = 12/3

y =4

d ) x = 2y

3x + 5y = 55 x= 2y

x= 2 × 5

x= 10

3 (2y) + 5y = 55

6y + 5 y = 55

11y = 55

y= 55/11

y=5

e) 4x + y = 7

2x - 5y =9

y = 7 - 4x

y = 7 - 4 × 2

y = 7 - 8

y= -1

2x - 5 (7 - 4x ) = 9

2x - 35 + 20x = 9

2x + 20x = 9 + 35

22x = 44

x = 44/22

x = 2