Răspuns :

Răspuns:

a)7x+3 < 2x + 10  | -3 -2x

  5x < 7 | :5

  x < 7/5

b)2 -3x [tex]\geq[/tex] 4x -12  | +12 +3x

  14 [tex]\geq[/tex] 7x  | :7

  2 [tex]\geq[/tex] x  | x(-1)

  x [tex]\leq[/tex] 2

c)5(3 -2x) [tex]\leq[/tex] 15

  15 - 10x [tex]\leq[/tex] 15 | -15

  -10x  [tex]\leq[/tex] 0 |  : (-10)

  x  [tex]\leq[/tex] 0

d)4(8-3x) > 12 -2x

  32 -12x > 12 -2x | +12x -12

  20 > 10x | :10

  2 > x | x(-1)

  x < 2

  Spor la teme!

Răspuns:

a) 7x+3<2x+10 =7x-2x < 10-3 ⇒ 5x <7 ⇒ x <7/5

b) 2-3x ≥ 4x-12 = 3x+4x ≥ 12+2 ⇒ 7x ≥ 14 ⇒x ≥ 14/7≥  2

c)5(3-2x)≤15 = 2x ≤ 15-15 ⇒2x ≤ 0⇒x ≤0

d)4(8-3x)>12-2x=2x+3x > 32-12 ⇒5x > 20 ⇒x > 20/5 > 4