Question

Resolva as inequações no conjunto dos números Naturais. a) 2x + 5 < – 3x +40 b) 6(x – 5) – 2(4x +2) > 100 c) 7x – 9 < 2x + 16

Answer 1

a) 2x + 5 < -3x + 40 => 2x + 3x < 40 - 5 => 5x < 35 => x < 35/5 => x<7

b) 6(x-5) - 2(4x + 2) > 100 => (6x -30) - (8x + 4) > 100 => 6x - 30 - 8x - 4 > 100
    6x - 8x > 100 + 30 + 4 => -2x > 134 => -x > 134/2 => -x = 67 ou x = -67

c) 7x - 9 < 2x + 16 => 7x - 2x < 16 + 9 => 5x = 25 => x = 25/5 => x = 5