RAFAELLASANTOS780GO RAFAELLASANTOS780GO Matemática Respondido resolva as expressões a)15-(8-10+5)+(4-6)= b)(-7)-(-7)+(-15)+6-(+2)=c)(+3)+(+9)-(+4)-(-8)+(+5)=d)6+3-4-2-6-12+4-12+2=