Question

realiza (+8)-(+9)+(-7 )= (-12)-(-3)+(-5)= (+9)+(-13)-(-21)= (-17)+(+5)-(+20)=

Answer 1

(+8)-(+9)+(-7 )=8-9-7= -8
(-12)-(-3)+(-5)= -12+3-5=-14
(+9)+(-13)-(-21)= 9-13+21=17
(-17)+(+5)-(+20)=-17+5-20=-32