Respostas

2013-05-13T20:11:19-03:00

x + y = 20

x - y = 4

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2x=24

x = 12

 

x+y =20

12+y=20

y = 8

 

ax+2y=32

12a+2.8=32

12a+16=32

12a=16

a=16/12

a = 4/3

 

3x-by=20

3.12-8b=20

36-8b=20

8b=36-20

8b=16

b=16/8

b = 2

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