109.

(a+3) 7=a*7+3*7=7a+21              (x-y)10=10x-10y              (a-b)*x=ax-ay

a (a+b)=a²+ab                                  (a+b-c)2=2a+2b-2c         (a-b)(-6)=-6a-(-6b)

x (x-y+c)=x²-xy+cx                         (a-b)5a=5a²-5ab

110.

(-20)(x+y)= 2x+(-2y)                      (7+3y-x²y)(-2xy)=(7+y³-x² y) (-2xy)=y+7

3ab (a²-2a+1)=4a²-5a+1a+b        2a(x+y)=20x+2ay

(x²+2xy+y²)(-12xy³)=3x+3y⁴*-qx+-qy    21a²b⁵(a³-4ab²-b2)=

(-abc)(ab+ac+bc)=-3a*3c*3b                    -ac(a+2c)=ac+2ac

111.

2(a+b)+4(a+b)=2a+2b+4a+4b                   4(x-y)+7(x-y)=4x-4y+7x-7y

4-2(x+1)=2(1-x)               =2*(2x+1=1x)                   2a-3(b-a)=3*b-3a

2(a-b)-3(a+b)=                 2a-2b-3a+3b                      a(x-y)-b               (x+y)=ax+ay-bx+by

3a²-a(3a-4b0-2(b-4a)=  5a²-4b-2b-8a                     2ab(a+2b)-3ab²(a-4)=3ab+4ab-4ab²-12ab

112.

a (b-c)+b(c-a)+c(a-b)=(ab-ac)

a(b+c-bc)-b(c+a+ac+c (b-a)