Odpowiedź:
a) -(2x-7y+5)+(-3x-4+7y)= -2x+7y-5+(-3)-4+7y=-2x+14y-12
b)(4a -2b)- 6a -(7b -8)=4a-2b -6a -7b+8= -2a-9b-8
c) 3a- ( 5b- 18) +5a +9= 3a - 5b+18 +5a+9=8a-5b+27
d) 4 * (-2- 5x+ 8y)= -8 -20x +32y
e) -8* ( 5- 6x +2xy)- 10xy= -40+48x-16xy-10xy=-30+48x-26xy
f)-