Question

sistemas de equações, alguém me ajuda?​

Answer 1

Resposta:

i) x+y= 2x(2)

4x-2y=5

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2x+2y= 4

4x-2y=5

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6x = 9

x= 9/6

x= 3/2

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x+y= 2

3/2+y= 2

3+2y= 4

2y= 4-3

y= 1/2

S={(3/2,1/2)}

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j) 2x+y= 4

x+y= 11 x(-1)

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2x+y=4

-x-y=-11

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x= -7

x+y= 11

-7+y= 11

y= 11+7

y= 18

S={(-7,18)}

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k) x+2y=10

x-3y=0 x(-1)

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x +2y= 10

-x+3y=0

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5y= 10

y= 10/5

y= 2

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x+2*2= 10

x+4= 10

x=10-4

x= 6

S={(6,2)}

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l) 2x- 5y= 3 x(4)

4x-2y=0 x(-2)

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8x -20y= 12

-8x +4y= 0

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-16y= 12

y= -12/16

y= -3/4

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2x-5y= 3

2x- 5(-3/4)=3

2x+15/4= 3

8x+15=12

8x= 12-15

8x= -3

x= -3/8

S={(-3/8,-3/4)}