Resposta :
4)
x+y x-y
8 4
0 -10
-21 -15
6 8
5)
a)
-3+5-6 =-4
b)
-20+9-4-1-6 = -22
c)
-18+9+17+20 = 28
d)
16-8-4+16+4+8 = 32
6)
-18-19+50-13 = 0
Letra D
4)
x+y x-y
8 4
0 -10
-21 -15
6 8
5)
a)
-3+5-6 =-4
b)
-20+9-4-1-6 = -22
c)
-18+9+17+20 = 28
d)
16-8-4+16+4+8 = 32
6)
-18-19+50-13 = 0
Letra D