Question

Resolva os sistemas de equacoes:
A) x+y=11
x- y=3

B) x-y=1
x+y=9

C) x -y=16
x+y=74

Obs: colocar todas as contas pfv

Answer 1

A)
 x+y=11
 x-y=3
 2x=14
 x=14/2
x=7

x+y=11
7+y=11
y=11-7
y=4

(7,4)

B)

x-y=1
x+y=9

2x=10
x=10/2
x=5

x-y=1
5-y=1
-y=1-5
-y=-4 vezes (-1)
y=4

(5,4)

C)
x-y=16
x+y=74

2x=90
x=90/2
x=45

x-y=16
45-y=16
-y=16-45 
-y=-29 vezes (-1)
y=29

(45,29)

Answer 2

Ola Giprin

A) 

x+y=11
x- y=3
2x = 14
x = 7
7 + y = 11
y = 4

B)

x-y=1
x+y=9

2x = 10
x = 5
5 + y = 9
y = 4

C)

x -y=16
x+y=74

2x = 90
x = 45

45 + y = 74
y = 74 - 45 = 29

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