form 2 MATH

係ax-ay-by+by定係ax-ay-by+by
ax-ay-by+by
=ax-ay
=a(x-y)


ax-ay-bx+by
=a(x-y)-b(x+y)
=a(x-y)+b(x-y)
=(a+b)(x-y)

如果唔明email me=]

ax-ay-by+by

=ax-ay

=a(x-y)

ax-ay-by+by
=a(x-y)

你有冇打錯ar?
ax-ay-by+bx
=a(x-y)+b(x-y)
(x-y)(a+b)

ax-ay-bx+by
=a(x-y)-b(x-y)
(x-y)(a-b)

ax-ay-by+by
=a(x-y)-by(1+1)

ax-ay-by+by
= ax-ay
= a(x-y)
圖片參考：http://tw.yimg.com/i/tw/ugc/rte/smiley_4.gif

ax-ay-by+by
=a(x-y)

你係咪打錯左呀
係咪應該ax-ay-bx+by?
如果真係既話應該咁做

ax-ay-bx+by
=a(x-y)-b(x-y)
=(x-y)(a-b)

ax-ay-by+by
= a(x-y)//

-by+by = 0 唔洗寫"