4.
a)
[tex]m:6 =k+5 \ \ \rightarrow \ \ m = 6k+5\\\\Zatem:\\\\m-5 = 6k+5-5 = 6k+0, \ \ TAK\\\\m+5 = 6k+5+5 = 6k+10=6k+6+4 = 6(k+1)+4, \ \ NIE\\\\m-11 = 6k+5-11 = 6k-6 = 6(k-1)+0, \ \ TAK\\\\m+25 = 6k+5+25 = 6k+30 = 6(k+5)+0, \ \ TAK[/tex]
b)
[tex]n:13 = k+10 \ \ \rightarrow \ \ n = 13k+10\\\\Zatem:\\\\n-10 = 13k+10-10 = 13k+\underline{0}\\\\n+1 = 13k+10+1 = 13k + \underline{11}\\\\n+3 = 13k+10+3 = 13k+13 = 13(k+1)+\underline{0}\\\\n+5 = 13k+10+5 = 13k+15 = 13k+13+2 = 13(k+1) +\underline{2}[/tex]
