a)9x+x-31 = 19
10x = 19+31
10x = 50
x = 50/10
x = 5
b)x+x+3 = 3x-9
2x-3x = -9-3
-x = -12
x = 12
c) 2x+12 = -4x-14
2x+4x = -14-12
6x = -26
x = -26/6 simplificando por 2
x = -13/2
d) 15+5x = 30+10x
5x-10x = 30-15
-5x = 15
x = -15/5
x = -3
❤️ Espero ter ajudado ❤️
04/08
