Question

Simplify the sum 4/m+9 + 5/m2 - 81

Answer 1

The answer to the question is 4m-31/(m-9)(m+9)

Answer 2

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)