Jawabanmu

2014-09-01T14:12:52+07:00
1. -9x+4y+(-5x)-9y = -9x-5x+4y-9y =-14x-5y
2. -4x+6y-(4x-8y) = -4x-4x+6y+8y =-8x+14y
3. k=2(p+l)
=2(3x+6+2x)
=2(5x+6)
=(10x+12)cm

maaf ya kalau salah :)