Mathématiques

Question

Pouvez vous m'aider sur le sytème :
y=-2/3x+5/3

y=5/4x+1

2 Réponse

  • y=-2/3x+5/3
    y=5/4x+1


    -5/4x = 1-y
    x = -4/5 +4/5y

    donc
    y = -2/3(-4/5+4/5y ) +5/3
    y = 8/15 -8/15y +25/15
    y = -8/15y +33/15
    y+8/15y =33/15
    15/15y+8/15y = 33/15
    23/15y = 33/15
    y = 33/15 *15/23
    y = 33/23

    x = -4/5 +4/5y
    x =-4/5 +4/5 (33/23)
    x = -4/5 +132/115
    x = -92/115 +132/115
    x =40/115
    x = 8/23

  • y=-2/3x+5/3
    y=5/4x+1
     

    -5/4x = 1-y
    x = -4/5 +4/5y

    donc 
    y = -2/3(-4/5+4/5y ) +5/3
    y = 8/15 -8/15y +25/15
    y = -8/15y +33/15
    y+8/15y =33/15
    15/15y+8/15y = 33/15
    23/15y = 33/15
    y = 33/15 *15/23
    y = 33/23

    x = -4/5 +4/5y
    x =-4/5 +4/5 (33/23)
    x = -4/5 +132/115
    x = -92/115 +132/115
    x =40/115
    x = 8/23

Autres questions