Question

resolver, no universo Rio as seguintes inequacoes: a ) 2 (3-x)+x>1+2 (x-1) b) 4 (x+1)-5<2 (x+3)

Answer 1

Olá Menininho, 

a ) 2 (3-x)+x > 1+2 (x-1)
    6 - 2x + x > 1 + 2x - 2
    6 - 2x + x-1 -2x +2 > 0
    7 - 3x > 0 
    7 > 3x
    x < 7/3


b) 4 (x+1)-5<2 (x+3)
4x+4 - 5 < 2x + 6
4x - 2x < 6 + 5
2x < 11
x < 11/2

=)

Answer 2

a)
2(3-x)+x>1+2(x+1)

6-2x+x>1+2x+2

-2x+x-2x>1+2-6

-3x>-3
(troca o sinal)

3x<3
x<3÷3
x<1

S= {x ∈ R / x < 1 }

b)

4(x+1)-5<2(x+3)

4x+4-5<2x+6

4x-2x<6+5-4

2x<7

x< $\frac{7}{2}$

S= { x ∈ R / x < $\frac{7}{2}$}