3 ( x - 2y ) - 5 [ 2/5x - ( 3y - 2x ) ]
=3x - 6y -5 [ 2/5x - 3y +2x ]
=3x - 6y - 2x + 15y - 10x
=-9x + 9y
答案為選項C
13. 化簡 3( x -2 y )-5[ 2/5 x -(3 y -2 x ..-阿摩線上測驗