resoudre les equations suivantes a) x+9=0 b) 3x=12 c) x=-x d)8x-30=0 e)5x+3=-4-15 f) 2(5y+4)=3(1-y)+8y

a)x+9=0
x=-9

b)3x=12
x=12/3
x=4

c)x=-x
2x=0
x=0

d)8x-30=0
8x=30
x=30/8

e)5x+3=-4-15
5x=-22
x=-22/5

f)2(5y+4)=3(1-y)+8y
10y+8=3-3y+8y
5y=-5
y=-5/5
y=-1

a) x+9=0
x = -9

 b) 3x=12
x = 12/3
x = 4

c) x=-x
x+x =0
2x =0
x =0/2
x =0

 d)8x-30=0
8x =30
x =30/8
x = 15/4

e)5x+3=-4-15
5x = -19-3
5x = -22
x = -22/5

f) 2(5y+4)=3(1-y)+8y
10y+8 = 3-3y+8y
10y -5y = 3-8
5y = -5
y = -5/5
y = -1