Answer:
[tex]i) -5a^2bc * 6ab * 8abc^2\\\\-5*6*8*a^2*a*a*b*b*b*c*c^2\\\\-240*a^4*b^3*c^3\\\\-240a^4b^3c^3[/tex]
[tex]ii) -3x^2y * (5y - xy)\\\\= -3x^2y*5y - (-3x^2y *xy)\\\\-3*2*5*x^2*y*y + 3*2*x^2*x*y*y\\\\-30x^2y^2 + 6x^3y^2\\\\\\iii) x^2y^2z^2 * (xy - yz +zx)\\\\x^2y^2z^2*xy - x^2y^2z^2*yz + x^2y^2z^2*zx \\\\x^3y^3z^2 - x^2y^3z^3 + x^3y^2z^3\\\\\\iv) (p + 6) * (q - 7)\\\\p*q - 7 *p + 6*q - 6*7\\\\pq -7p + 6q - 42[/tex]
[tex]v) (2x + 7) * (x^2 - 5x + 6)\\\\2x * x^2 - 5x*2x + 6 * 2x + 7*x^2 - 7 * 5x + 7 * 6\\\\2x^3 - 10x^2 + 12x + 7x^2 - 35x + 42\\\\2x^3 - 3x^2 - 23x + 42[/tex]
[tex]vi) (x + y + 5) * (2x - 2y - 3)\\ \\x*2x - x*2y - 3*x + 2x*y - y*2y - y*3 +5*2x - 5*2y - 5*3\\\\2x^2 - 2xy - 3x + 2xy - 2y^2 - 3y + 10x - 10y - 15\\\\2x^2 - 2y^2 + 7x - 13y -15[/tex]
