7) Answer = [tex]-24x^8y^{11}[/tex]
[tex]\left(8x^4y^2\right)\left(-3x^4y^9\right)[/tex]
[tex]=-8x^4y^2\cdot \:3x^4y^9[/tex]
[tex]=-24x^4y^2x^4y^9[/tex]
[tex]=-24x^8y^2y^9[/tex]
[tex]=-24x^8y^{11}[/tex]
8) Answer = [tex]-30y^6[/tex]
[tex]2y\left(-5\right)y^2\cdot \:3y^3[/tex]
[tex]=-30yy^2y^3[/tex]
[tex]=-30y^{1+2+3}[/tex]
[tex]=-30y^6[/tex]
9) Answer = [tex]-6x^4y^5[/tex]
[tex]\left(-2xy\right)\left(xy\right)\left(3x^2y^3\right)[/tex]
[tex]=-2xyxy\cdot \:3x^2y^3[/tex]
[tex]=-6xyxyx^2y^3[/tex]
[tex]=-6x^4yyy^3[/tex]
[tex]=-6x^4y^5[/tex]
