Respuesta :
factor
m^2-81=(m-9)(m+9)
multiply other equation by (m-9)/(m-9)
4(m-9)/(m^2-81)+5/(m^2-81)
(4(m-9)+5)/(m^2-81)
(4m-36+5)/(m^2-81)
(4m-31)/(m^2-81)
m^2-81=(m-9)(m+9)
multiply other equation by (m-9)/(m-9)
4(m-9)/(m^2-81)+5/(m^2-81)
(4(m-9)+5)/(m^2-81)
(4m-36+5)/(m^2-81)
(4m-31)/(m^2-81)