Question

Determinati numerele natural care verifica inegalitatile : 
a ) 18x - 14 ≥ 2 * ( 3x + 5 )
b ) 243 : ( x - 4 ) > 9 si x : 5 ≥ 2
c ) ( 2 * x + 3 * x ) ) : 5 ≤ 8 
d ) [ 4 * ( 13 * 5 + 5 * x ) ] : 36 < 30 

Answer 1

a)18x-14≥6x+10
18x-6x≥10+14
12x≥24
x≥24:12
x≥2
x={2,3,4..}
b)x-4>243:9
x>27+4
x>31
x={32,33..}
x:5≥2=>x≥5x2=.x≥10
x={10,11,12..}
c)2x+3x≤8*5
5x≤40
x≤40:5
x≤8
x={0,1,2..8}
d)4(65+5x)<30x36
260+20x<1080
20x<1080-260
20x<820
x<820:20
x<41
x={0,1,2..40}