Question

Resolvendo as atividade com dúvidas
x + 9 = - 1?
X + 28 = 11?
X - 39 = 5?
10 = x + 8?
15=x+20?

Answer 1

x+9 = -1
x = -1 - 9 = -10

x+28 = 11
x = 11 - 28
x = -17

x -39 = 5
x = 5 + 39
x = 44

10 = x + 8
-x = 8 -10
-x = -2
x = 2

15 = x+20
-x = 20 - 15
x = -5