Question 764096

{{{yz+4z = z-y^2}}}


{{{z(y+4) = z-y^2}}}

{{{z(y+4)-z =-y^2}}}

{{{z((y+4)-1) =-y^2}}}

{{{z(y+4-1) =-y^2}}}

{{{z(y+3) =-y^2}}}

{{{z =-y^2/(y+3)}}}