Respostas

2014-08-03T10:32:43-03:00
1* figura
X/75=50/60
60x=3750
 x=3750/60
 x=25

2*figura
26/X=20/40
20x=1040
   x=52

3*figura
2X-2/3X+1=4/7
12x+4=14x-14
12x-14x=-14-4
-2x=-18
 x= -18/-2
 x=9