How do you multiply #(-2z^2 + 6z - 1)(- 4z^2)#?

1 Answer
Apr 10, 2015

We use the Distributive Property of Multiplication to solve this.

In general, #color(blue)((a+-b)*c = (a*b) +- (a*c)#

#(-2z^2 + 6z - 1)(- 4z^2)#

#= (-2z^2)*(-4z^2) + 6z(-4z^2) - (-4z^2)#

#= (-2*-4)(z^2*z^2)+ (6*(-4))(z*z^2) + 4z^2#

In general,#color(blue)( a^m*a^n = a^(m+n)#

#= (8)(z^(2+2))+ 6(-4)(z^(1+2)) + 4z^2#

#= 8z^4 + (-24)(z^3) + 4z^2#

#color(green)(= 8z^4 - 24z^3 + 4z^2#