Répondre :
bonjour:je suis en 4eme
5x+11=18
5x=18-11
5x=7
x=7/5
x=1,4
2x+2x7=-1
2x+14=-1
2x=-1-14
2x=-15
x=-15/2
x=-7,5
jespere t'avoir aider :)
5x + 11 = 18
5x = 18 - 11
5x = 7
x = 7/5
x = 1.4
2(x + 7) = -1
2x + 14 = -1
2x = -1 - 14
2x = -15
x = -15/2
x = -7.5
voila :)