PLease explain how to do this

Question

Add or Subtract
(m^2-m+3)+(m-1)

Answer 1

( m ^ 2 - m + 3 ) + ( m - 1 ) =

m ^ 2 - m + 3 + m - 1 =

m ^ 2 - m + m + 3 - 1 =

m ^ 2 + 2

( m ^ 2 - m + 3 ) - ( m - 1 ) =

m ^ 2 - m + 3 - m - ( - 1 ) =

m ^ 2 - m - m + 3 + 1 =

m ^ 2 - 2 m + 4