64p2-q2=(8p-q)(8p+q)
1-81b2=(1-9b)(1+9b)
16c2d2-9=(4cd-3)(4cd+3)
25q4-169t6=(5q2-13t3)(5q2+13t3)
121-(a+3)2=(121-a-3)(121+a+3)=(118-a)(124+a)
36x2-169=0
36x2=169
x2=169:36
x2=169/36
x=13/6=2 1/6
64p2-q2=(8p-q)(8p+q)
1-81b2=(1-9b)(1+9b)
16c2d2-9=(4cd-3)(4cd+3)
25q4-169t6=(5q2-13t3)(5q2+13t3)
121-(a+3)2=(121-a-3)(121+a+3)=(118-a)(124+a)
36x2-169=0
36x2=169
x2=169:36
x2=169/36
x=13/6=2 1/6