Question

Me ajudem a responder essas

Answer 1

a) x-y
5-(-4)
5+4=9

b) 3x+a
3(2)+6
6+6=12

c) 2x+m
2(-1)+(-3)
2-3=-1

d) a-b
9-(-12)
9+12= 21

2) d= n (n-3) /2
d= 15 (15-3) /2
d= 15 (12) /2
d= 180/2
d= 90