Question

alguém me ajuda???? é urgente
1) X-3y=1
2x +5y = 13
2) 2x + y = 10
x + 3y = 15
3) x + y = 2
3x + 2y = 6
4) x + y =3
2x +3y = 8
5) 2x + 3y=9
4x - 5y=7​

Answer 1

Resposta:

a) x-3y= 1 x(-2)

2x+5y=13

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-2x+6y=-2

2x+5y=13

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11x= 11//x=11/11=1

2*1+5y=13// 2+5y=13//5y=13-2//

y = 11/5

b) 2x+y=10 x(-3)

x+3y=15

-----------------

-6x-3y= -30

x+3y=15

-5x= -15// x= -15/-5=3

3 +3y=15// 3y=15-3//y= 12/3= 4

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c) x+y= 2 x(-2)

3x+2y=6

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-2x-2y=-4

3x+2y= 6

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x= 2 /// x+y=2// 2+y=2//y= 2-2=0

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d) x+y=3 x(-3)

2x+3y=8

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-3x-3y=-9

2x+3y= 8

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x= -1 /// x+y= 3//-1+y= 3// y= 3+1=4

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e) 2x+3y=9 x(-2)

4x-5y=7

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-4x-6y= -18

4x-5y= 7

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-11y= -11 //y=-11/-11= 1

y=1

4x-5*1=7// 4x=7+5//4x=12//x=12/4=3