Chapter 7 - Section 7.3 - Multiplying and Simplifying Radical Expressions - Exercise Set - Page 533: 123

a) $-8x$ b) $-8\sqrt[3] 2$

a) we have $4x-12x$ Thus, Take the common terms out, we have $4x-12x=4x(1-3)=4x(-2)=-8x$ when we combine same terms we will have the result : $-8x$ b) we have $x=\sqrt[3] 2$ Thus, $4x-12x=4 \sqrt[3] 2 -12 \sqrt[3] 2= \sqrt[3] 2(4-12)=-8\sqrt[3] 2$ when we combine same radicals we will have the result : $-8\sqrt[3] 2$