Question

Resolva em R cada inequação.
a) 5x + 8 > - 12
b) 4x + 5 < 2x
c) 6x – 4 >=3x + 5
d) 3 – 5x <=8

Answer 1

a) 5x + 8 > - 12==> 5x > 4 ==> x > 4/5
b) 4x + 5 < 2x ==> 4x-2x< - 5 ==> 2x < - 5 ==> x < - 5/2
c) 6x – 4 >=3x + 5 ==>= 6x-3x>= 5+4 ==> 3x >= 9 ==>= x >= 3
d) 3 – 5x <=8 ==> - 5x <= 8 - 3 ==> -5x<= - 5(-1) ==<= 5x >= 5 ==> x >= 1

Answer 2

a) 5x + 8 > - 12
5x > - 12 - 8
5x > - 20
x > - 20/5
x > - 4

b) 4x + 5 < 2x
4x - 2x < - 5
2x < - 5
x < - 5/2

c) 6x - 4 >= 3x + 5
6x - 3x >= 5 + 4
3x >= 1
x >= 1/3

d) 3 - 5x <= 8
- 5x <= 8 - 3
- 5x <= 5 .(-1)
5x >= - 5
x >= - 5 / 5
x >= - 1