Упростите (m-3)(m+3)-m(m+2)

Question

Упростите
(m-3)(m+3)-m(m+2)

Answer 1

(m-3)(m+3)-m(m+2)=m^2-9-m^2-2m=-9-2m

Comments

там есть вариант а)-2m-9 ; б)9-2m ;в)2m-9 ;г)2m+9

Answer 2

(m-3)(m+3)-m(m+2)=m^2+3m-3m-9-m^2-2m=-9-2m