Answers

2014-03-28T14:50:14+01:00
3x+4y=5 (a) 2X-3y=9 (b) ¬Ľ x=(9+3y)/2 (c) (c) dans (a) 27 +9y+8y=10 Y=-1 (d) (d) dans (a) X=3
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2014-03-28T21:13:04+01:00
3x + 4y =5
2x - 3y =9

2 X 3x + 4y =5
3 X 2x -3y =9
6x +8y =10
6x - 9y = 27
 ELIMINATE
17y= -17
y=-1
substitute in eqn 1
3x +4(-1) = 5
3x - 4 =5
3x =5+4
3x = 9
divide both sides by 3
x =3
1 5 1