11) (4+6x)(3xy-2z)= 12xy-8z+18x^2y-12xz
12) (7x-6)(2y-4xz)= 14xy-28x^2z-12y+24xz
13) (5x-6)(7xy+3z)= 35x^2y+15xz-42xy-18z
14) (5-7x)(4y+3xz)= 20y+15xz-28xy-21x^2z
15) (3xy-2z)(4y+3xz)= 12xy^2+9x^2yz-8yz-6xz^2
16) (4y-3xz)(5xy-2z)= 20xy^2-6yz-15x^2yz+6xz^2
17) (7xy+3z)(2y-4xz)= 14xy^2-28x^2yz+6yz-12xz^2
18) (3xz-2y)(4y+3xz)= 12xyz+9x^2z^2-8y^2-6xyz= 6xyz+9x^2z^2-8y^2
19) (4y-3xy)(5xy-2y)= 20xy^2-8y^2-15x^2y^2+6xy^2= 26xy^2-8y^2-15x^2y^2
20) (5x-6y)(7xy+3x^2)= 35x^2y+15x^3-42xy^2-18x^2y= 17x^2y+15x^3-42xy^2
1) 3(2x-4)= 6x-12
2) -5(4-6x)= -20+30x
3) (7x-6)8= 56x-48
4) (9-8x)(-5)= -45+40x
5) 7y(8x-6)= 56xy-42y
6) (5x-6)7y= 35xy-42y
7) -6y(5-7x)= -30y+42xy
8) (5-6x)(-4y)= -20y+24xy