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3 years ago

Cuanto es (2x+2y=20) (-2x-6y=-52) con método de igualación y método de suma y resta

Mathematics

1 answer:

Nataly_w [17]3 years ago

6 0

x =2 y =8

2x + 2y=20

2x=20-2y

x=10-y

Ahora len la otra ecuacion remplazamos x por (10-y)

-2(10-y)-6y=-52

-20+2y-6y=-52

2y-6y= -32 (-52+20= -32)

-4y=-32

-y=-8

y=8 x=10-y x=2

2*2+2*8=20

4+16=20

-2*2-6*8= -52

-4-48= -52

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