Question

0,45x + 0,20x + 21 = x

Answer 1

0.65x+21=x
0.65+x=-21
1.65x=-21 (-1)
x=21:1.65
x=12.72

Answer 2

Resposta:

0.65x+21=x

0.65+x=-21

1.65x=-21 (-1)

x=21:1.65

x=12.72

Espero ter ajudado :D