x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c

x-y=p+q

x+y=p-q

x-y=p-q

both a & c