Jawabanmu

2014-08-28T18:50:34+07:00
A. ( 10x2y) - (10x10) = 20y-100
b. (y+5) x (5r-1) = 5ry+ (-1y) + 25r -5 =5ry+25r-y-5
c. (7-2y)x(2r-7) = 14r+(-49)-4ry+14y = 14r+14y+4ry-49