solve ((−(r*(v-k*cos(δ))-k*sin(δ)*x))/(r^(2)+x^(2)))=((p*cos(δ)+q*sin(δ))/(k)) and ((k*sin(δ)*r+(v-k*cos(δ))*x)/(r^(2)+x^(2)))=((p*sin(δ)-q*cos(δ))/(k)) for p and q