Question

Calcule as inequaçoes 2x+4<20

Answer 1

2x + 4 <  20
2x < 20 - 4 
2x < 16
  x < 16/2
  x < 8

Answer 2

2x+4<20      passando o 20 pro outro lado

2x+4-20<0

2x-16 < 0      igualando a zero acharemos a raiz

2x-16=0
2x=16
x=16/2
x=8

x<8