How do you multiply \frac { 4z ^ { 2} + 24z } { 3z ^ { 2} - 9z - 12} \cdot \frac { z ^ { 2} - 4z - 5} { z - 4} 4z2+24z3z29z12z24z5z4?

2 Answers

Perhaps some one else can spot how to simplify this further.

(4z(z^2+z-30))/(3(z-4)(z-4))4z(z2+z30)3(z4)(z4)

Explanation:

Just playing with formats to start with. Looking for things to cancel out.

(4z(z+6))/(3(z^2-3z-4))xx((z+1)(z-5))/(z-4)4z(z+6)3(z23z4)×(z+1)(z5)z4

(4z(z+6))/(3(z+1)(z-4))xx((z+1)(z-5))/(z-4)4z(z+6)3(z+1)(z4)×(z+1)(z5)z4

(4z(z+6))/(3cancel((z+1))(z-4))xx(cancel((z+1))(z-5))/(z-4)

(4z)/3xx((z+6)(z-5))/((z-4)(z-4)

(4z)/3xx(z^2+z-30)/((z-4)(z-4)

(4z(z^2+z-30))/(3(z-4)(z-4)

Dec 22, 2016

(4z(z+6)(z-5))/(3(z-4)(z-4))

Explanation:

(4z^2+24z)/(3z^2-9z-12)*(z^2-4z-5)/(z-4)

(4z(z+6))/(3(z^2-3z-4))*((z+1)(z-5))/(z-4)

(4z)/3*((z+6))/((z+1)(z-4))*((z+1)(z-5))/((z-4))

(4z(z+6)(z-5))/(3(z-4)(z-4))