Bonjour
a)
5 + x = 19
x = 19 - 5
x = 14
b)
y - 3 = 15
y = 15 + 3
y = 18
c)
- x + 8 = 5
- x = 5 - 8
- x = - 3
d)
5x = 2
x = 2/5
e)
12y = - 30
y = - 30/12
y = - 5/2
f)
5x + 3 = 13
5x = 13 - 3
5x = 10
x = 10/5
x = 2
g)
13 + 3y = 4
3y = 4 - 13
3y = - 9
y = - 9/3
y = - 3
h)
5x - 3 = 2x + 6
5x - 2x = 6 + 3
3x = 9
x = 9/3
x = 3