5x+4<16
5x<16-4
5x<12
x<16/5
4x-12≤15
4x≤15+12
4x≤27
x≤27/4
3 la puterea x ≤27
27/3=9
9/3=3
rezulta ca 3 ori 3 ori 3=27, deci 3 la puterea 3 = 27, deci x=3
5 la puterea 2x+1 < 125
125/5=25
25/5=5
deci 5 ori 5 ori 5 = 125, rezulta ca 5 la puterea 3 = 123, deci:
2x+1=3
2x=3-1
2x=2
x=2/2
x=1
7x-3≤5x+13
7x-5x≤13-3
2x≤10
x≤10/2
x≤5
2x+4<x+16
2x-x<16-4
x<12
