Question

Sistema de equacoes simultaneas do 1° grau 2x+3y=47 e x+y=20

Answer 1

2X + 3Y = 47

X + Y = 20;

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Y = 20 - X;
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2X + 3(20-X) = 47;

2X + 60 - 3X = 47

-X = -13 (-1);

X = 13 ;




2(13) + 3Y = 47

3Y = 47 - 26

3Y = 21;

Y = 21/3

Y = 7;

Answer 2

2x+3y=47
x+y=20

2x+3y=47
x+y=20 .(-3)

2x+3y=47
-3x-3y=-60

-x=-13
x=13
13+y=20
y=7