Rodolpho Cabral
23/01/2015 • 11:32
420 - 140 = 280
(210 - x) + x + (140 - x) = 280
-2x + x + 350 = 280
-x = 280 - 350
-x = 70
x = 70
(210 - x) + x + (140 - x) = 280
-2x + x + 350 = 280
-x = 280 - 350
-x = 70
x = 70