Réponses

2013-03-03T18:48:54+01:00
A) 2x-5 = 3x+24. Donc par translation, x = -29.
b) 15-6y = 2y - 4 Dc 19 = 8y, y = 19/8.
c) -11-9x = 11+5x Dc x = -22\14.
D) 28-8y = 7-24 + 12y. Soit x= 45/20
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2013-03-03T18:55:20+01:00

a) 2x-5 = 3(x+8)

   2x -5 = 3x +24

   2x -3x = +5 +24

   -x = 29

    x = --29

 

15 -6y = 2y -4 (y +1)

15 -6y = 2y -4y -4

15 -6y = -2y -4

-6y +2y = -15 -4

 -4y = -19

   y = -19/-4 y = 19/4

 

1 -3 (4-3x) = -11 +5x

1 -12 +9x = -11 +5x

-11 +9x = -11 +5x

+9x -5x = +11 -11

  +4x = 0

 

4(7+2y) = 7 -4(6-3y)

28 +8y = 7 -24 +12y

8y -12y = -28 +7 -24

-4y = -45

y= -45/4