efetue,
(+25)+ (-20)-(+15) - (-5)-
30-(35-40)+(-2+5) =
4-(4+5-8)
74 +1-20)+(-15)+(+14) + (-74 +626)+(-1)
19 – 15.(-4)-[(-4) + (+5)]=
27+ (-15).(+2)
7-(-2)-8. (+5) 5 (-2)-
7+15(-3) - 2 (-3)
(-5)-(-8)-2) = [(-3) + (-1)]
24+ [-15-(-8+4)
15-(12+3)-[18-(14-25]​