Tìm x , biết:a.  x +  = 2,5 ×1,5   ,

a) x+45=2,5×1,5        x+45=3,75                 x=3,75−45                x=2,95

b)  4,775−x=4,775+3,6×0,01−11004,775−x=4,775+3,6×04,775−x=4,775                x=4,775−4,775                x=0