Math....Question

2x-6y/3y-x
= 2x-6y/-(x-3y)
=2(x-3y)/-(x-3y)
=2/-1
=- 2/1
2. -x^2+1/x+1
=- (x)(x+1)/x+1
= -x
3. 2p-10r/r^2 ÷ 30-15r/6pr
= 2p-10r/r^2 ÷ 6pr/3p-15r
= 2(p-5r)/r^2 ÷ 6pr/3(p-5r)
= (2)(6p)/(r)(3)
= (2)(2p)/r
= 4p/r




2007-11-07 12:09:14 補充：
第1題：=- 2/1= -2