Réponse :
4x=12
4x÷4=12÷4
x = 3
-6x=34
-6x÷6=34÷6
-x=[tex]\frac{34}{6}[/tex]
x=[tex]\frac{-34}{6}[/tex]
x-5 = 15
x-5+5=15+5
x=20
x+8=15
x+8-8=15-8
x=15
4x-7 = 2x+13
4x-2x-7+7=2x-2x+13+7
2x=20
x=10
-6x+3=3x+15
-6x-3x+3-3=3x-3x+15+3
-9x=17
x=-[tex]\frac{17}{9}[/tex]