... x a, X 0, 25 x X = 1 20 05 x 2008 10 05 20 05 x( 2007 + 1) 10 05 = 2006 x 2007 1007 ( 20 05 + 1) x 2007 1007 20 05 x 2007 + 20 05 10 05 20 05 x 2007 +1000 = =1 20 05 x 2007 + 2007 1007 20 05 x 2007 +1000 ... 1007 20 05 x 2007 +1000 X 0, 25 x X = 3 X x ( 1- 0, 25 ) = X x 0, 75 = - 1 ,5 X x 0, 75 = 1 ,5 X = 1 ,5 : 0, 75 X=2 b, 17 ,56 - x X = 20 - 6,7 17 ,56 - x X = 13,3 x X =17 ,56 13,3 x X = 4,26 x X = 4,26 ... BH = 25cm Tớnh di tng MQ + MK II Đáp án Tính nhanh 12,48 : 0 ,5 x 6, 25 x x 2 x 3,12 x 1, 25 : 0, 25 x10 12,48 x x 6, 25 x x 2 x 3,12 x 1, 25 x x 10 4x5x2 10 Tìm X 12 :x+ 12 :x = 12 :x = 11 15 x =...